error while trying to install itunes 9 on vista

Hello,  

For the past 2 weeks I have been trying very hard to install itunes 9 on vista x64bit.  I always get a cabinet file error while trying to install and it is really annoying.  I have tried pretty much everything I could think of.  I installed it from different internet browsers, did complete uninstalls and redownloading things but to no avail.  The error I always get is "The cabinet file 'AppleMobileDeviceSupport.cab' required for this installation is corrupt and cannot be used. This could indicate a network error, an error reading from the CD-Rom, or problem with this package."  I cancel the installation and then it tries to install Quicktime and I get a cabinet file error for that as well.  I was on the phone with Apple for a while and they determined it was a problem with my machine and I would have to ask Dell.  I figured I'd start in the forums.  If anyone knows anything that would be super!  I am coming to my wits end about this.  I just want to use my ipod with my machine!  thanks