It's really hard to say what could be the problem, not sitting at your PC.

Have you tried test if your friends og next door people or others on the same network has problems?

If I were you, I'd try figure out if the error was with the network or your PC, either try the PC from another network, or try another PC on yours.

If it's the same with another PC, I'd contact your network admin. If it's not, the error is with your PC.

You could try delete your Temp folder (that is a different one from the temporary one) but you might loose some settings and setups and other.

Other than that... no idea sorry. I'd reinstall if another PC had no problems from your line, but it depends if the site is that important to you of course.

Let me know what happens and if you figure it out. Best of luck!