msn driver scanWhy did Firefox, uTorrent, AIM and Thunderbird stop working but not IE, MSN Messenger or Yahoo Messenger?

Yesterday, or the day before, Firefox, Thunderbird and Utorrrent (almost entirely) stopped connecting to the Internet, but not IE, Yahoo Messenger or MSN. Utorrent, after many minutes of the arrows turning red, allows one torrent to start downloading around 45 kbps, but none of the other torrents work.

I did an antivirus scan with avast and it found two trojans in a folder that apparently have nothing to do with anything with this, since they've been there for a while and not given me any problems I noticed. I turned off my firewall, reset the TCP settings, restored IE's default security, did the Windows Internet connection repair (disabling and renabling the driver) and that didn't do anything either. I also rebooted, and that did nothing either.

I also checked my startup routine and nothing showed that indicated some malicious software, although recently I did untick SPIRUN (supposedly a Creative related program even though I don't use Creative software which has this as it's "path": Rundll32 SPIRun.dll,RunDLLEntry), NVcpldaemon amsn driver scannd nvmedia center (nvidia stuff apparently). I was using privatefirewall, but turned it off because it kept interferring with things that were obviously harmless like a program I use called supercopier, which I was using recently to transfer data from one drive to another and ran into little problems like corrupted sectors on the drive (not my main drive but an external one) and two file names that were too long (which is bizarre since they previously weren't "too long" to transfer to the drive I transfered them too, the one with the corrupted sectors).

I looked up stuff on the net to see if anything would simultaneously disable firefox and utorrent, but only found seperate references to them not being able to connect to the net, including IE being able to connect but not firefox.

Does anyone know what would knock out these programs together, or strangely make it so that utorrent can only work with a single torrent? I'd rather solve this mystery than wipe out my drive or do a system restore since no doubt it's affecting more peomsn driver scanple than just me and could save people a lot of time if a quicker and less messy solution could be found to fix this problem then doing a system restore or reinstallation.

At 2:14 AM, hours later, Thunderbird started working again, but Firefox, uTorrent and AIM still won't though, and uTorrent won't download anything anymore.
u r kiddin! it never happened
simply , and sorry for saying that , but did u try to uninstall those not working program and install them again , if it still not working .

then the problem in the windows it self , plz reinstall ur windows and install ur driver and before opening any partition , just install the anti virus and scan the whole PC for any viruses and Trojans and clear it . then u can start working normally , before u reinstall the windows , plz burn ur anti virus on a CD so u don't need to open any partition when u reinstall ur windows avoiding contacting with any viruses or Trojans.

hope i helped here , have a nice day :)