Cannot connect to internet

I have a Sony Vaio laptop (VGN-FW PCG-3D3L) with an internal Intel wireless adapter (link 5100) running Vista. Everything was working fine one night. Next morning when I turned the computer on, I couldn't connect to the internet! I'm using Chrome to connect.

What I've tried:
-- Spent an hour on the phone with Optimum support checking home modem/wireless (Netgear) router. (Other machines...Desktop computer and Surface tablet connecting to internet just fine) No fix.
-- checked Device Manager. Both network devices do NOT have exclamation points and reported as "device functioning properly"

I went out and bought a Belkin wireless adapter and installed it. My computer is still not connecting to the internet.

My (home) network says the machine is connected "with limited access" and shows a red X from the Vaio to the internet.

There must be something going on with the settings but I don't have a clue where to look or what to adjust and I don't want to make matters worse.

If someone could help get my computer connected to the internet again I would be eternally grateful. I spend my evenings using my laptop to access mail, games, social venues, shop, etc and I'm LOST without the internet!!

Thanks for any assistance.
Luni

 

Plodr,
Do you mean by restoring a backup (of the hard drive)? Or going back to a restore point? If the latter, I don't know how to do that. I haven't changed anything yet. I didn't want to muddy the waters.
Thanks
Luni

 

Plodr,
Thanks for the instruction link on system restore. When I went to system protection to pick a restore point, only one existed....4/1 when I installed the Belkin USB wifi adapter. No sense restoring that one...the issue already existed.

I'm showing I'm connected "with limited access"..no internet access.

I tried to connect to the internet at a hotspot and couldn't connect.

I tried connecting with an Ethernet cable (my old wired connection)...still no access.

Today I noticed that my desktop, which can connect to the internet, has an exclamation point on the networking map.

Do you think this is a software or hardware issue?
Luni