.Net install problems

Okay...first I was getting updates for .NET thru windows update that would not install. So I uninstalled and tried to reinstall but everything I've tried doesn't work. I downloaded the cleanup tool and ran it and it seemed to go well, but no version would install. I have tried everything I can find on it at Microsoft support sites. I don't have any idea what to do next. Anyone had this experience? Do I even need this program? What happens if I don't have it?

Dell Dimension 8400 desktop (originally with Windows XP)
Windows 7 Home Premium 32 bit (fully updated)
2 GB memory
500 GB hard drive
Wireless home network w/HP laptop (Windows 7 Home Premium 64 bit)
D-Link dir628 router

I've not heard of this before but perhaps you could provide some more information so I or another member can do more research.

Is it definitely a problem with the install failing or does it fail while downloading (ie has the file actually made it to your harddrive)?

Could you tell us which .Net install you are trying version # (a URL where you got it would be great)?

Some .Net installs are considered part of the OS so I am wondering if any damage was done on uninstall. You said you used an uninstall tool, where did you get it? On Microsoft.com I see a tool for 3.0, 3.5, and 4.0.

Have you installed W7 Service Pack 1 beta? Service packs & even windows updates can lock in components.

I am putting the link here to .Net 4.0 for myself & anyone else that may be trying to help (and that page offers other links to older versions) but I see no link to an uninstaller tool.

I'm really confused now after all I've tried but I will try to get it all straight...
I ran Windows Update and there were 4 updates available:
Silverlight KB2164913
.Net Framework 4 Client profile for Windows 7 x86 KB982670
Update for 2007 MS Office system KB2284654
Security update for MS Office XP KB2288608

It went thru the motions of download and started install then:
failed: 4 updates
error codes: 643 and 89B (both unknown errors)

I think the update service is working because on 9/15 both the Office updates listed above showed up along with 3 other updates which did install.

I uninstalled Silverlight and .NET framework and downloaded .Net versions from Microsoft.com download page but none of the versions would install (See: http:\\support.microsoft.com/kb/923100/ ) This is where I found the link for the removal tool.

dotnetfx_cleanup_tool
http://blogs.msdn.com/b/astebner/arc...08/406671.aspx

I don't know what to try next, so any suggestions will be appreciated.

That tool is from 2005. .net 4.0 wasn't even available and because .net 4 builds on 3.5 and 2 that tool may have seriously messed up things.

I would try recovery to a restore point that is prior to both the install or uninstall. Type "restore point" in the search of windows start to restore your computer to an earlier time. If you don't find any restore points you might try booting up from the windows recovery disc you were told to create when W7 first ever booted up.

UPDATE: well I do see it was updated in 2009 but I still don't trust it and I would try the above.