Sorry about that Sharon, if you mean the MSKB route .... at least it eliminates something.
I think Phil has a valid point, as someone who has Roxio on board -- my recollection is that you can re-downoad by logging in to your "account" on their website.
I just did a Google on your error message about missing file UM.MSI and you are very far from alone.
I have written the following in response to your message saying the filters thing did not work but I see the extent that you are working with Phil so work on with him but if all else fails here is some more guidance. Note that the problem is known to many users and to Roxio.
As for the "can't uninstall because another is running" for me that is both a pointer to what is wrong and something that brute force (eg SAFE MODE and or Revo Uninstaller might deal with!)
As I say, stick with Phil untikl ....
I take no responsibility for this but here is one offered solution:
http://answers.microsoft.com/en-us/windows/forum/windows_xp-performance/ummsi-missing-file-error/95613598-9c5f-e011-8dfc-68b599b31bf5
which refers people to Roxiios's FAQ
Update Manager (Service) issues and resolutions
Since I don't know whether your version matches or not or whether there is a more uptodate fix from Roxio it seems you should ask them.
For example I see that Sevice Pack 2 Update for EasyCreator 2010 includes << Resolves script errors when using the Update Manager. >> so if that is your version, or if it was and you might have something left over when Upgrading as you said ata the beginning, then that might explain the problem.
Please understand that because something occurs when a Norton product is present and not when it is not does not automatically mean there is something wrong with Norton! It may seem odd but we have lived through more than one incident here where this seemed obvious but turned out to be because Microsoft and Norton were in step with a change in a system file but a third party utility was not that it took all lthree for the crash to occur but updating the third party application fixed the problem!
My feeling is that you should certainly check with Roxio but that because you have other possible issues from Avira I would do the following with a reboot in between each step.
Make sure all traces of Avira are removed -- check for advice
Make sure all traces of Roxio are removed -- check for advice
Make sure all traces of Norton are removed -- there is a new tool that will remove it, clean up and reinstall the most recent version for you.
Reinstall Roxio.
I hope that helps.
See what others have to say.