DIGIT-ARC read-only archive · snapshot: July 23, 2026

Ethernet Port of laptop fried. Any alternatives?

67 posts · originally from https://geek.digit.in/community/threads/ethernet-port-of-laptop-fried-any-alternatives.173623/

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desijoker Original post #1
May 9, 2013 at 6:31 PM
Hi...due to thundering, my wireless router and my laptop's ethernet port fried yesterday.
I use broadband with CAT5 cable(kinda LAN cable only).
Now dunno how to use internet :( .. I bought usb to ethernet adopter..but loose connection every few seconds..dunno what to do :(
any solution or advice?
btw i have hp dv5 series laptop.

UPDATE:
Got a replacement for my wireless router..Today also thunderstorm started..so I switched off the switch..but forgot to pull the plug.within few seconds
sme shitty thunderstorm hit near my place and I lost my 2TB hard disk..new replaced wireless router.. JBL speakers and all USB ports,HDMI,firewire,memory card slot of my lappy but dunno how motherboard survived and laptop is working fine!!!
Tell me if it is not my bad luck!
Had collected so many stuffs on that 2TB HDD..lost everything within a second. btw all the plugs were connected to 2 surge protectors..but still they couldnt protect them :( :( :( :(
The Incinerator
May 9, 2013 at 6:55 PM
Go WiFi

Buy a TP-LINK TL-WR841N 300Mbps Wireless N Router - TP-LINK: Flipkart.com
RCuber
RCuber #3
May 9, 2013 at 6:57 PM
check drivers for the converter. also check if HP covers warranty on lightning damage.

for router you need to buy a new one. most companies wont replace router damage caused by lightning.
The Incinerator
May 9, 2013 at 7:03 PM
Lightning Damage = Act of God = Not Covered
D
May 9, 2013 at 7:48 PM
Well I had bought a new Asus wireless router 6 days ago :( ..damn...
I gave it to Asus service centre ..they said they will let me know by tomorrow. but i didnt mention that lightening caused it..
btw Wifi does work and i can browse internet through it but sometimes speed drops down like hell..and it happens frequently..
RCuber
RCuber #6
May 9, 2013 at 7:57 PM
cross your fingers that they just think its a defective unit and replace it with a new one. wifi issue might be from a interference from another wifi network, just change the channel in the router and try.
The Incinerator
May 9, 2013 at 8:00 PM
Well I had bought a new Asus wireless router 6 days ago :( ..damn...
I gave it to Asus service centre ..they said they will let me know by tomorrow. but i didnt mention that lightening caused it..
btw Wifi does work and i can browse internet through it but sometimes speed drops down like hell..and it happens frequently..

Thats smart. Talk to HP too see if they change the Motherboard. Is it under warranty?
D
May 9, 2013 at 8:07 PM
Thats smart. Talk to HP too see if they change the Motherboard. Is it under warranty?

nope..not under warranty..motherboard looks fine but somehow only Ethernet brain fried up..lan port shows continuous orange light..no blink at all..it doesnt matter whether cable is connected or not.
Seriously bad luck man..actually extra voltage passed through CAT5 cable from broadband ppl and my whole electronic equipment is connected to 2 surge protectors :( so there is no way it came through electric connection...seriously bad luck...
The Incinerator
May 9, 2013 at 8:11 PM
I connect my LAN through a Belkin Gold surge protector,it stops any act of god coming through the CAT5 too! I thought its useless, now Im glad that I bought it.
D
desijoker #10
May 9, 2013 at 8:13 PM
and can i sue broadband ppl if i proved that their cable caused the problem and my loss? :p

I connect my LAN through a Belkin Gold surge protector,it stops any act of god coming through the CAT5 too! I thought its useless, now Im glad that I bought it.

I also googled for that few hrs ago...it is costly but now it i know it is damn important..!! God knows how to screw us in many ways!
The Incinerator
May 9, 2013 at 8:13 PM
Nah.......Act of God again...........no court will entertain you!:wink:
D
desijoker #12
May 9, 2013 at 8:17 PM
Nah.......Act of God again...........no court will entertain you!:wink:

hmm...but they couldve installed Belkin diamond or titanium surge protectors also ryt for their switch:wink:
I mean seriously.
The Incinerator
May 9, 2013 at 8:20 PM
hmm...but they couldve installed Belkin diamond or titanium surge protectors also ryt for their switch:wink:
I mean seriously.

They could have, but they saved costs. They surely have lost some equipment too,maybe.
D
desijoker #14
May 9, 2013 at 8:20 PM
and any other alternative for LAN port? usb to lan adapter seriously doesnt work..
S**t..it started raining again!! :( ...now I am so scared of rain man...
The Incinerator
May 9, 2013 at 8:22 PM
and any other alternative for LAN port? usb to lan adapter seriously doesnt work..
S**t..it started raining again!! :( ...now I am so scared of rain man...

The USB and Wifi are the only option.
D
desijoker #16
May 9, 2013 at 8:28 PM
Hmm...its a 4yr old lappy..dont want to invest much..but even now runs all latest games at medium settings..dunno what to do with it.
Thanks guys for replying..hopefully God will show mercy this time and my router will be replaced :)
dashing.sujay
May 9, 2013 at 9:42 PM
I don't think any kind of surge protector will protect you from lightning.
RCuber
RCuber #18
May 9, 2013 at 9:59 PM
^^ some rubber would ;)
pratyush997
May 9, 2013 at 11:22 PM
Lightning Damage = Act of God = Not Covered
I'm calling Kanji bhai! :D


On topic
@OP try getting that port fixed by HP and IMO you will need new router :D
Always connect via Wi-Fi :D
D
desijoker #20
May 9, 2013 at 11:45 PM
On topic
@OP try getting that port fixed by HP and IMO you will need new router :D
Always connect via Wi-Fi :D

HP charges alot man..thats the problem.they have checking charge...then opening charge..then repairing charge..dunno what all charges...
will go to SP road in blore...charges will be lower
image
image #21
May 9, 2013 at 11:54 PM
Do you have PCMCIA slot in your laptop? You can get something like this:

*www.fixitnow.us/images/dlink%20pcmcia%20adaptor.jpg
pratyush997
May 9, 2013 at 11:58 PM
HP charges alot man..thats the problem.they have checking charge...then opening charge..then repairing charge..dunno what all charges...
will go to SP road in blore...charges will be lower
My Hp (Pavilion Tx 1000 Tablet PC) had some Gpu issues! They asked 23k for MoBo replacement LOL.
A local dealer was selling original MoBo (refurb maybe) for 5k few years ago :D
D
desijoker #23
May 10, 2013 at 12:09 AM
My Hp (Pavilion Tx 1000 Tablet PC) had some Gpu issues! They asked 23k for MoBo replacement LOL.
A local dealer was selling original MoBo (refurb maybe) for 5k few years ago :D

my lappy screen had some problem..hp ppl quoted 15K plus fitting charges...I paid local dealer 6k and I had a original hp screen along with bill and warranty..all are same man..even dell..thats how these big companies make money on services..
DO you guys think that LAN port can be repaired? coz I am sure if i Go to HP ppl, those ppl wont even look at it and will tell me to change motherboard..Local dealers will first see then he will figure it out that one resistor is burnt and fix it and then will tell me that he had to change something something and will charge me more..and those guys dont even allow us inside when they are working on it.

Do you have PCMCIA slot in your laptop? You can get something like this:

*www.fixitnow.us/images/dlink%20pcmcia%20adaptor.jpg

yup I have that port in my lappy..I saw it in ebay..asked a seller also whether it will work with CAT5 or not..he said he have no idea..it will be on my risk.
These are costly..but definitely btr than usb to ethernet adapter..
The Sorcerer
May 10, 2013 at 2:01 AM
No surge protector gives 100% protection. It may prevent something, but against lightning- no. In all honesty, you should have gone wi-fi.
pratyush997
May 10, 2013 at 2:38 AM
Well, fortunately your lappy's mobo didn't fried.
D
desijoker #26
May 10, 2013 at 11:55 AM
No surge protector gives 100% protection. It may prevent something, but against lightning- no. In all honesty, you should have gone wi-fi.

Hmm...true..but wifi used to give less speed..and sometimes pinging problem..so used LAN port..

Well, fortunately your lappy's mobo didn't fried.

seriously man..I was lucky in that case..if mobo had gone then had to buy a new lappy only..again big investment.
Nerevarine
May 10, 2013 at 12:01 PM
I lost a laptop and a modem to lightning..
F**k the rain :/
You can use USB2Ethernet or PCMCIA2Ethernet cards..
They are available everywhere, just take a look around..
Use ebay if you cant find
D
desijoker #28
May 10, 2013 at 12:06 PM
I lost a laptop and a modem to lightning..
F**k the rain :/
You can use USB2Ethernet or PCMCIA2Ethernet cards..
They are available everywhere, just take a look around..
Use ebay if you cant find

I had bought usb2ethernet..but it disconnects every few seconds..dunno whether loose connection or it cant take the load or something..and i googled this problem and came to know that it is very common in usb2ethernet..
now only PCMCIA2ethernet is the only option..will be ordering today itself..atleast will try it..
But can LAN port be repaired? It is in same main circuit of mobo ryt..
Nerevarine
May 10, 2013 at 12:34 PM
No, service centers rarely repair issues like these...
Maybe if you are lucky, they might replace the Mobo but if not, you are out of luck :(
D
desijoker #30
May 10, 2013 at 12:39 PM
it is out of warranty..so replacing motherboard will be damn costlier and not worth it for my lappy.
Nerevarine
May 10, 2013 at 1:06 PM
yep. laptop mobo replacement can go as high as 8k-12k..
in my case it was 8k.. so i decided to screw laptops and i bought a pc :lol:
D
desijoker #32
May 11, 2013 at 1:10 AM
Got a replacement for my wireless router..Today also thunderstorm started..so I switched off the switch..but forgot to pull the plug.within few seconds
sme shitty thunderstorm hit near my place and I lost my 2TB hard disk..new replaced wireless router.. JBL speakers and all USB ports,HDMI,firewire,memory card slot of my lappy but dunno how motherboard survived and laptop is working fine!!!
Tell me if it is not my bad luck!
Had collected so many stuffs on that 2TB HDD..lost everything within a second. btw all the plugs were connected to 2 surge protectors..but still they couldnt protect them :( :( :( :(
pratyush997
May 11, 2013 at 1:46 AM
Got a replacement for my wireless router..Today also thunderstorm started..so I switched off the switch..but forgot to pull the plug.within few seconds
sme shitty thunderstorm hit near my place and I lost my 2TB hard disk..new replaced wireless router.. JBL speakers and all USB ports,HDMI,firewire,memory card slot of my lappy but dunno how motherboard survived and laptop is working fine!!!
Tell me if it is not my bad luck!
Had collected so many stuffs on that 2TB HDD..lost everything within a second. btw all the plugs were connected to 2 surge protectors..but still they couldnt protect them :( :( :( :(

:eek: that's some serious issue.
Freaking bad luck.
Nerevarine
May 11, 2013 at 3:24 AM
*www.thinkdigit.com/forum/networking/159932-ethernet-port-busted.html


No one replied to me at that time *Forever alone*
D
desijoker #35
May 11, 2013 at 9:46 AM
:eek: that's some serious issue.
Freaking bad luck.

:(
damn couldnt sleep last night..can we retrieve hard drive contents? hard drive is spinning but no computer is recognising it
The Incinerator
May 11, 2013 at 10:38 AM
You have to replace the PCB of the HDD, IMO. So get hold of some repair guys who do that in your city.
D
desijoker #37
May 11, 2013 at 10:44 AM
You have to replace the PCB of the HDD, IMO. So get hold of some repair guys who do that in your city.

just now checked online and came to know that warranty is still there..will be going to seagate service centre in few mins. but i really want the data..they might replace it with a new one..but i really wanted data from the hard drive.. :(
The Incinerator
May 11, 2013 at 11:03 AM
They will charge you a Boeing 747 for 2TB data retrieval! Better look locally to restore data before getting a certified repaired HDD from seagate as replacement.
D
desijoker #39
May 11, 2013 at 6:40 PM
gave the hard drive to seagate ppl..they said replacement if all condition for replacment under warranty is valid..but all data is lost..cant do anything now..
regarding laptop, new IC has to be installed...just a temp solution..wont change whole motherboard..
speakers are also to be repaired..dunno whether they are repairable or not
G
May 11, 2013 at 8:04 PM
You must be joking right? If you had turned off switch keeping adapter plugged...theres no way thunderstorm can damage something in your pc...sound like your smps is giving bad supply...also belkin gives lifetime warranty on power adapters.

Moreover you can sue belkin if it has not protected against surge.
pratyush997
May 11, 2013 at 8:13 PM
You must be joking right? If you had turned off switch keeping adapter plugged...theres no way thunderstorm can damage something in your pc...sound like your smps is giving bad supply...also belkin gives lifetime warranty on power adapters.

Moreover you can sue belkin if it has not protected against surge.
His Username :D

jk
D
desijoker #42
May 11, 2013 at 9:11 PM
You must be joking right? If you had turned off switch keeping adapter plugged...theres no way thunderstorm can damage something in your pc...sound like your smps is giving bad supply...also belkin gives lifetime warranty on power adapters.

Moreover you can sue belkin if it has not protected against surge.

btw i use laptop..and yes i had switched the button off and yes thunderstorm can overcome the resistance of the plug and can pass through even if the switch is off..i googled and it has happened to me. It is not like i dunno whats happening..cmon..I am not that dumb :p
Gollum
Gollum #43
May 11, 2013 at 9:21 PM
Got a replacement for my wireless router..Today also thunderstorm started..so I switched off the switch..but forgot to pull the plug.within few seconds
sme shitty thunderstorm hit near my place and I lost my 2TB hard disk..new replaced wireless router.. JBL speakers and all USB ports,HDMI,firewire,memory card slot of my lappy but dunno how motherboard survived and laptop is working fine!!!
Tell me if it is not my bad luck!
Had collected so many stuffs on that 2TB HDD..lost everything within a second. btw all the plugs were connected to 2 surge protectors..but still they couldnt protect them :( :( :( :(

wow talk about bad luck.

If you laptop is within warranty then call HP after a week and say it happened today morning.

:(
damn couldnt sleep last night..can we retrieve hard drive contents? hard drive is spinning but no computer is recognising it

is it a USB HDD that worked well with your notebook?
if so then you can try opening the case and get the bare HDD out. Chances are you might be able to connect the HDD to a normal desktop sata cable and still be able to use the HDD
D
desijoker #44
May 11, 2013 at 9:53 PM
wow talk about bad luck.

If you laptop is within warranty then call HP after a week and say it happened today morning.



is it a USB HDD that worked well with your notebook?
if so then you can try opening the case and get the bare HDD out. Chances are you might be able to connect the HDD to a normal desktop sata cable and still be able to use the HDD

laptop is not under warranty..and I gave the HDD to seagate service center for replacement..i thought to open it up but thought it might void the warranty..now i wish i should've tried atleast..
gagan_kumar
May 11, 2013 at 10:38 PM
btw i use laptop..and yes i had switched the button off and yes thunderstorm can overcome the resistance of the plug and can pass through even if the switch is off..i googled and it has happened to me. It is not like i dunno whats happening..cmon..I am not that dumb :p
it happened with my television through the cable connection while i was on leave

laptop is not under warranty..and I gave the HDD to seagate service center for replacement..i thought to open it up but thought it might void the warranty..now i wish i should've tried atleast..

u know u could have still recovered imp data......... if it was not fried
D
desijoker #46
May 11, 2013 at 10:45 PM
it happened with my television through the cable connection while i was on leave



u know u could have still recovered imp data......... if it was not fried

yea...well i asked a hard disk repair guy and he said 5k for 1tb of recovery if possible..i showed my middle finger and came off..
pratyush997
May 11, 2013 at 10:56 PM
^ LOL, That's really expensive :/
Nerevarine
May 11, 2013 at 11:02 PM
forget the data and move on..
Use cloud backup if you have the broadband :D
D
desijoker #49
May 11, 2013 at 11:07 PM
forget the data and move on..
Use cloud backup if you have the broadband :D

bought broadband for that only:-D..2 days of broadband ethernet port fried..and 4th day rest all!
Either this broadband or Asus product was "Shani" for me i guess:p
Anyways whats gone is gone..ordered belkin gold surge protector today...hopefully will get a new hard disk..speaker repair will cost alot..too much expenses this week man!
gagan_kumar
May 11, 2013 at 11:37 PM
no dude
try connecting via usb
maybe it will work
D
desijoker #51
May 11, 2013 at 11:50 PM
no dude
try connecting via usb
maybe it will work

OMG OMG OMG....usb ports on my lappy suddenly began to work!!! I have no clue how it happened..How is it possible? seriously!!
I have windows 8 and linux...i normally use windows..but after this incident was using linux and now rebooted to windows and it was working!! I have no idea how it happened...wow...miracle?:-D:oops::mrgreen::oops:
saved me some money!! might be temporary..but it proves that they are not fried..even if they were dunno how they came back to life..i did practically everything..
gagan_kumar
May 11, 2013 at 11:55 PM
c i told u it will work XD :mrgreen:
D
desijoker #53
May 12, 2013 at 12:01 AM
c i told u it will work XD :mrgreen:

lol..ethernet via usb doesnt work.. i mean loose connection most of the time..but i just plugged in my wireless mouse receiver and and saw cursor moved a lil...my heart skipped a beat then saw it working...Seriously how is it possible? scientifically? loose connection in main board? or deep sleep ?
if usb can work then ethernet too..in ethernet port orange like constantly glows..no matter what..that means there is current in it..and even windows and linux recognizes the LAN...
Gollum
Gollum #54
May 12, 2013 at 2:27 AM
try this.
remove battery and ac adapter from unit
hold power button for 30 seconds
start the unit with just ac adapter
this will drain all power from the unit and most of the devices should start to work.
W
westom #55
May 12, 2013 at 3:41 AM
if usb can work then ethernet too..in ethernet port orange like constantly glows..no matter what..that means there is current in it..and even windows and linux recognizes the LAN...
At this point, understand a path that surge took from cloud to earth. If a surge is incoming on one wire (ie AC electric), then it was also outgoing via some other wire (ie ethernet). If both an incoming and outgoing paths do not exist, then no surge exists. Any damaged part must have both that incoming and outgoing path. An concept we all learned in elementary school science.

Some parts can be in that path and not be damaged. Understand how damage happens. A current is flowing from the cloud to distant earthborne charges. Current is everywhere in that path, simultaneously. Only one or some items in that path fail. What was the path? And what was in that path?

Second, your problems are why better computer manufacturers provide comprehensive hardware diagnostics for free. An OS does everything possible to ignore and work around failures. Sometimes, things that appear to be good are defective. And sometimes things that appear defective are good. Diagnostics mean hardware is identified; without confusion created by the OS.

Third, routine is to have even direct lightning strikes without damage. That was well understood even 100 years ago. Demonstrated 23 times annually atop the Empire State Building. And 40 times annually atop the WTC. Munitions dumps with direct strikes and no explosion. Your telco CO's $multimillion switching computer, connected to wires all over town, suffers about 100 surges with each storm. How often is your town without service for four days after a thunderstorm? Never? Because well proven protection also costs less money. And is rarely known by so many only informed by retail advertising, hearsay, or speculation.

You should also be installing the well proven solution so that protection even standard in ethernet ports (ie thousands of volts) is not overwhelmed by a rare and destructive transient.

An open power switch is nothing but a direct connection from a destructive surge into electronics. Even unplugging is an extremely unreliable solution.

What was the incoming and the other outgoing path via your computer? At this point, you should have a pretty good idea.

One final point. Damage is often on the outgoing surge path. Many use speculation to assume a damaged port must be an incoming path. Remember, you are dealing with electricity. That means both an incoming and another outgoing path existed to have damage. Protectors that somehow magically stop or absorb energy are only for surges that typically cause no damage. They are why so many 'assume' protection from direct strikes is not possible. Know why you have damage AND learn how to avert future damage. Because protection even from directly lightning strikes typically costs about $1 per protected appliance. But requires information I have not seen posted here.
D
desijoker #56
May 12, 2013 at 4:29 PM
try this.
remove battery and ac adapter from unit
hold power button for 30 seconds
start the unit with just ac adapter
this will drain all power from the unit and most of the devices should start to work.

tried that already...still only orange light glows..but windows still says device working properly..From what I learned online is that NIC has brain and a ear for listening to packets...but the problem is brain cant hear anything even when sound is coming..now i dunno how to solve this problem..
Gollum
Gollum #57
May 12, 2013 at 6:46 PM
tried that already...still only orange light glows..but windows still says device working properly..From what I learned online is that NIC has brain and a ear for listening to packets...but the problem is brain cant hear anything even when sound is coming..now i dunno how to solve this problem..

tried updating the BIOS along with uninstalling the device from device manager. Are you sure the ethernet port on the other end is okay?[router]
D
desijoker #58
May 12, 2013 at 6:52 PM
tried updating the BIOS along with uninstalling the device from device manager. Are you sure the ethernet port on the other end is okay?[router]

i have tried uninstalling and reinstalling the device..no luck and router is working just fine on other laptops..
BIOS which i have is the latest one...nothing was released after that...
W
westom #59
May 13, 2013 at 7:50 AM
i have tried uninstalling and reinstalling the device..no luck and router is working just fine on other laptops.
Again, that confusion was defined by this sentence:
Second, your problems are why better computer manufacturers provide comprehensive hardware diagnostics for free. An OS does everything possible to ignore and work around failures. Sometimes, things that appear to be good are defective. And sometimes things that appear defective are good.

More details. NIC is a computer. A motherboard computer can talk to that NIC computer. A conversation means everything is OK - to the OS. But damage can exist between the NIC computer and ethernet cable. An NIC computer only knows what it sees: thinks no ethernet cable is connected.

Now, most ethernet NICs will tell you that and not the OS. A light exists on an NIC and on the router. When an NIC computer talks to the router computer, then lights on both units illuminate to report a good conversation - only to you. What do those lights report?

Motherboard BIOS is clearly irrelevant to all that. BIOS is a program that runs when the OS first boots. The OS then finds NICs, loads its own NIC drivers, and moves on without the BIOS.

What happens if a BIOS looks for the NIC during power up? BIOS also only sees an NIC computer; just like the OS also saw that NIC computer.

Meanwhile, what is and is not potentially damaged? What was in an incoming and outgoing surge path? That is necessary to avert future damage. And to also identify what may have been overstressed; may fail a month later.
gagan_kumar
May 13, 2013 at 2:49 PM
lol..ethernet via usb doesnt work.. i mean loose connection most of the time..but i just plugged in my wireless mouse receiver and and saw cursor moved a lil...my heart skipped a beat then saw it working...Seriously how is it possible? scientifically? loose connection in main board? or deep sleep ?
if usb can work then ethernet too..in ethernet port orange like constantly glows..no matter what..that means there is current in it..and even windows and linux recognizes the LAN...

what i meant was to try connecting hard disk via usb to backup
D
desijoker #61
May 13, 2013 at 4:55 PM
usb stopped working again...most probly it is not getting enough power...something is definitely wrong..a change in IC chip will solve usb problems but dunno how to resolve lan problem :(
W
westom #63
May 14, 2013 at 1:11 AM
... but dunno how to resolve lan problem
Described previously.
Now, most ethernet NICs will tell you that and not the OS. A light exists on an NIC and on the router. When an NIC computer talks to the router computer, then lights on both units illuminate to report a good conversation - only to you. What do those lights report?
dashing.sujay
May 14, 2013 at 2:52 AM
^I didn't want to say, but sir, your to-the-point posts are, apparently, not of the level which OP could get. (It's almost apparent till now, no offence to OP). Situation demands for a layman standard.

PS: You once helped me years back in a similar issue :), and I was pretty sure of your kicking in, when this thread started.
W
westom #65
May 14, 2013 at 4:32 AM
... your to-the-point posts are, apparently, not of the level which OP could get.
Described ethenet lights are equivalent to a car's "Check Engine" or "Temperature" light. And usually described in the instruction manual written for consumers.

"My car won't work." "Is the check engine light on?" A typical answer is usually humor to car mechanics.
D
desijoker #66
May 19, 2013 at 12:31 AM
Hi,
Can a laptop USB be fixed withing replacing motherboard?
the thing is my usb works.I mean only 1 port works out of 4. And sometimes others works for a minute then says usb not recognized.
I assume that it is getting low power hence it says that error.
So my Q is can we fix the usb port problem without replacing MoBo?
W
westom #67
May 19, 2013 at 2:35 AM
Can a laptop USB be fixed withing replacing motherboard?
You have no reason to suspect low power. Reasons why the USB ports are intermittent are many. OS has a system (event) log. That information provided to others means a better informed reply can exist.

Laptop USB hardware is typically repaired by replacing the laptop's motherboard. Some laptops have a peripheral card slot. A peripheral card that is a USB interface might be installed. Or spend bigger bucks for a USB hub that connects via the ethernet port.

Your questions and 'later discovered' symptoms are why better computer manufacturers provide comprehensive hardware diagnostics for free. Sometimes, things that appear to be good are defective. And sometimes things that appear defective are good. All your USB ports may be defective even though you see one working.

If your computer did not provide those diagnostics, then you have learned of one item that separates better laptops from inferior ones. Many if not all of your questions could have been answered by that diagnostic.

How to avert future damage and why that laptop is probably damaged also was summarized.

At this point, you are probably viewing a new computer. Learn from what happened to this one.