Windows 7: Required system software not installed

I just upgraded my acer aspire x1700 from vista home 64bit to win 7 64 bit. When I log on I get a dialog box titled "Required system software not installed". What it's asking for is framework 2.0. When I press OK, the dialog box goes away and everything works ok. I tried to install framework 2.0 but it said the system already had framework 3.5. So I tried to uninstall 3.5 and then load 2.0 but it still said system already had framework? My upgrade method was to run setup from within vista. I know it's best to do a clean install which I've done on by other 2 computers. I just wanted to see an upgrade process. Any ideas, this is anoying as He****
Thanks
jj

I've read several threads about .NET framework being unstable/unusable after upgrading from Vista to 7. I haven't found any solution on how to remove .NET, but it might be possible to identify the application/driver/hardware that's looking for .NET. Check out this thread:

.Net framework issues

If you have Visual Studio, take a look at this:

http://social.msdn.microsoft.com/For...-e9e4abb12e66/

Copy and paste to an elevated command prompt, then hit enter using the following command:

sfc /scannow

Do a Windows Update for good measure when that finishes.

(CCC needs 2.0 functioning well I believe. Don't know others.)

Thanks for all the replies and help. It was the Lexmark productivity suite. I un-installed it and downloaded win 7 driver from lexmark and installed without the productivty suite (I don't use it anyway). It's all good in the neighborhood