Windows XP + RRC 2.0 + .docx issue

I have some users that cannot open .docx documents in composer (specifically users running composer on windows XP). I was able to replicate the problem but I do not like the solution I came too.

This error comes up:

"Word cannot start the converter mswrd632.wpc"

Here is a link I found to correct the issue:

http://blogs.technet.com/wordonenotesupport/archive/2009/12/10/when-opening-the-word-document-users-are-getting-error-word-cannot-start-the-convertor-mswrd632-wpc-or-cannot-load-word-for-windows-6-0-files.aspx

I found a lot of articles telling me to delete registry keys (which does work) but most of my users are located remotely, under different contractors and most do not have administrative rights on their PC.

Is there another solution that doesn't involve editing registry keys?