Vista - Vista Internet Access Error

Hi friends!!

My name is Pankaj and I have recently joined this forum. I had genuine Vista Business x64 SP1 (downloaded from MSDN) running on my Dell Inspiron 1420 laptop running quite well, with all the necessary drivers. The performance was quite awesome as compared to the Home Premium x86 SP1 version supplied with the laptop from Dell.

It works great, but a wierd problem occurs after I install Visual Studio 2008 SP1 (downloaded from MSDN). Almost all x86 applications won't access the internet (i.e. updates and patches)...for e.g. Yahoo Messenger, Firefox 3, Skype, Java....etc and keep on crashing. It happens when after the VS2008SP1 gets updates from MS update. When I start Firefox, it opens up with a blank page and the progress bar shows done, even when I try to open any websites it shows the same message. Also, when closing, windows shows that Firefox has stopped working and the solution it shows is that DEP has blocked some features of Firefox. Now when I open Yahoo Messenger, it does not even load, it crashes directly, and MS error reporting does not give any feedbacks for the crash. Same is the case with Skype. Java does not update giving errors of server not reachable. Also IE7 x86 version crashes without any error.

I know that my internet is working quite well in that situation as I am able to access internet on the IE7 x64 version.

I have tried to google around for solutions, also searched on MSDN forums but in vain. I have also tried to disable DEP at the start of a fresh install (yes yes this has made me install the OS almost 4 times in a period of 1 month), but still I get the same problem.

I am a Masters student and I need to access VS2008SP1 and Java quite frequently, but also I am a casual gamer and play CS:Strike and NFS-MW online and on lan and using the entire 4GB of my latop with the x64 version makes the performance awesome...but because of this crashing problem I had to switch back to the x86 version a couple of days ago.

Please help me out as i really want to switch over to x64 version permanently...but these problems keep on switching me back...