Can't uninstall or update Silverlight 1 GDR 3 because silverlight.msi file is missing

[any ANONYMOUS forum user]

I'm just a user. Somehow, at some point in time, in some way unknown to me, I got Silverlight 1 GDR 3 (1.0.30401.0) installed on my desktop (Windows XP SP3). Now, I'm getting bugged to install an update through the Microsoft Windows Update web site, but the update is for Silverlight 1.0 and the silverlight.msi file is missing. I can't uninstall Silverlight 1.0 because, again, the silverlight.msi file is missing.

This also prevents me from updating to a newer version like Silverlight 2 GDR 1 (2.0.40115.0) because they require or attempt to uninstall Silverlight 1.0, which I can't do because, yet again, the silverlight.msi file is missing.

I did a file search on my entire computer and there is no silverlight.msi file because, yet again, it is missing. I cannot locate the 1.0 download on the web. Everytime I click on the main Silverlight web site, it informs me that 1.0 is properly installed (which it may be, but the silverlight.msi file is still missing).

I am using IE 8.0 if that makes any difference (I doubt it). And I have admin rights on my account.

Can somebody please point me to a download where I can obtain the silverlight.msi file or otherwise instruct me how to remove and/or reinstall Silverlight so that I can get back to normal operation here? Thanks!