Download a copy of latest driver. 

WIPE Out the driver from Device manager. reboot

Windows will install stock drivers > test 

If no go Install the driver you have downloaded. 

@janjalovy  -Always include exact PC model and version of Windows in your posts.

Inspiron i5 Windows10

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@janjalovy wrote:

Inspiron i5 Windows10

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Sorry but that's not a Dell PC model number.

If you don't know it, go to the Support site and enter your Service Tag. (Don't post it here.) The site will tell you the exact model number...

Sorry, that should have been a Dell Optiplex 3020, Windows 10.  Please let me know if you need any further info

@bradthetechnut  -  Actually the OP didn't mention the PC model in the OP.  The thread title was edited to include the model number, after it was finally posted, 3 days later. (Note the green "edit" in the OP.)

And the thread was subsequently moved from the Inspiron Desktop forum to the Optiplex Desktop forum...

You did state Optiplex 3020 Win10 in your 1st post.  What RoHe is getting at is what form factor/size is your Optiplex.  We usually let that go though if it doesn't seem relevant.  As for Win10, are you on 21H1?

Have you tried a different WiFi adapter?  I have a USB WiFi dongle that would do boot loop (constantly disconnect and reconnect).  Once I had Win10 up to 1809 or something like that, it quit boot looping.  Meanwhile, when it did do that, I got a different adapter and it worked.

Are you using a WiFi card or USB dongle?

The machine is infected with rootkit WINSOCK Malware.

3020 NIC drivers are native to the windows installation media.

https://docs.microsoft.com/en-us/windows/security/threat-protection/intelligence/rootkits-malware

If the problem persists, we strongly recommend reinstalling the operating system on a new drive . Then restore your data from a backup.

This is another reason to buy an OEM DVD because its read only and cannot be infected. You should buy this DVD now because they are not making anymore and the Refirbisher program was cancelled.  Once they are gone they will NEVER be available again.

https://www.newegg.com/microsoft-windows-10-pro-64-bit-reinstall-recovery-disc-only-no-license-key-included/p/N82E16832350238

New drive is not expensive.

https://www.amazon.com/dp/B07H2RR55Q/

Data can be recovered from the old drive with a DOCK.

https://www.amazon.com/dp/B07D6L5CJF

I originally had a Belkin Wireless G Plus Mimo dongle, which had worked faultlessly for as long as I have had the computer.  When it suddenly stopped I rushed out and bought a TP-Link T4U which installed but had to be re-installed each time I booted up.  A friend gave me his spare Realtec Nano 11 adapter which installed the driver but failed to find the adapter, so I then bought a Netgear AC 600 which again installed but failed to find the adapter.  I then swapped the original TP adapter for another one (in case there was a problem with the adapter itself), but it made no difference, so I have now swapped it for a TP T2U which, at least does find the adapter, even though I still have to re-install the software each time in order for the adapter to work.  As you can see, I have been rather busy!  TP themselves have tried to be helpful (unfortunately they are in the Far East which means that communication is very slow because of the huge time difference, but they have today directed me to another version of the software which I will try as soon as I re-boot the machine.

As for the Windows version, I am on 21H1

@janjalovy - When was last time you replaced the motherboard battery?

CR2032 3-volt lithium coin cell, ~$2.00.