Internet Explorer 8 Beta 2 - can't delete it!

[tonyryan]

I have the weirdest problem!

I have Internet Explorer 8 and downloaded the latest version of Beta 2 from Microsoft. When I try to run it I am told that there is an earlier version of Internet Explorer 8 on the system and that I must remove it. When I try to delete, rename, move or whatever to the file iexplore.exe I am told that I don't have permission, even though I am the administrator.

I then thought of a quick way around the problem and decided to download Firefox from Mozilla. The problem gets even weirder, as when the file downloads, it is nowhere to be seen, so I cannot run it. I have even tried downloading it to an external memory stick, but it just disappears after the 7Mb download finishes!

The initial problem started when I tried to open Internet Explorer recently and found that it simply opened and then immediately shut down again. Failing that it would open, a message would appear saying that it was not responding, and then Windows would shut it down.

I am running Windows Vista Business Version 6.0 Build 6001 Service Pack One. My version of Internet Explorer 8 Beta 2 is 8.0.6001.18241.

I have an awful feeling that this is a virus of some kind, but cannot find anything when I run the AVG products on my system.

Any help would be really appreciated!

Regards

Tony