Error with Microsoft Silverlight Update

Cleaning off old installers is not usually a big problem, most programs can still update even if an old installer is not present.  The same cannot be said for Microsoft Silverlight.  Having installed version 1.x back in early 2008, the installer had long since been deleted from their temp folder e:\ext37559\silverlight.msi.  All attempts to upgrade silverlight to version 2.0 failed.  It could not be removed or upgraded due to this file missing.

So what do you do:

1. Install the Windows Installer Cleanup Utility.
2. Highlight Microsoft Silverlight, then select remove.
3. if needed, type the following in a command prompt:

   reg delete HKLMSoftwareMicrosoftSilverlight /f

4. Then delete the “Microsoft Silverlight” directory under program files

This helped solve the update problem when the previous source had been removed.  Courtesy of: Bob Pomeroy’s Silverlight Blog

Another solution has been used by Curt (below in the comments):
This fixed my installation problem.
click start, run. type “cmd” and hit enter.
Locate the dir where silverlight.2.0.exe is
run “silverlight.2.0.exe /x:c:\temp /u” to extract the files to c:\ temp.
run c:\temp\install.exe to install Silverlight

Thanks for the info Curt!

Further to this solution by Curt, if the problem is with extracting the files from silverlight.2.0.exe. For example, you double click the installer and nothing seems to happen, or it starts to install then disappears, you can easily extract the install files out of silverlight.2.0.exe using a compression program such as winzip. This will allow you to extract the MSI which you can then use to install silverlight.