Disconnection problem

[aok]

When I got disconnected from the net, my PC would crash.

When I would start my PC without the net, my PC would crash.

I could sign on IM's, I could download from Steam, but I couldn't access the Internet.

The only way to shut my PC down when crashed was to hold the power button.

I decided to use System Restore. It actually worked.

BUT I need to know how to prevent this in the future.

Also, would it of been possible that my HDD could of been corrupted during the shut down by holding the power button?

[mrapoc]

So your pc basically crashes when not online and when online you cant access any websites..

Sounds like it could be malware/viral

Try a full scan with something like eset NOD32 (disable any other antiviruses whilst using another AV)

Do some full scans with superantispyware and malwarebytes

Iv had to do that to many systems hanging, the chances of corrupting your HDD are quite low, it will let you know usually if you have - should be fixable with a checkdisk.

[llwyd]

I would agree with mr apoc, either a virus or your firewall I would say. Maybe worth reinstalling TCPIP. If its XP find the most recent nettcpip.inf file and install it. If its vista you need to run netsh int ipv4 uninstall, reboot, netsh int ivp4 install, reboot.

May also be worth checking your bios for anything related to lan / wake on lan. I guess it's possible it was trying to go into a halt state when lan was lost.

[deepfried]

Agreed. Sounds like malware.