You may need to install from a new user account.
See this other thread for further help.
Replacement links for the final two which in the thread are the Dutch versions:
Thank you both for your replies. I have not tried any of them yet, so for now they are helpful.
I certainly hope the Avisory Tool does the trick. The steps in the other threads suggested appear to be quite complicated, certainly for the average user like my client. During testing, I remember this issue coming up, and the solution was quite straight forward - I just don't remember what it was. :-(
I'll reply back with what the solution was in this case, just to close the loop.
I have also this problem now trying to reinstall Adobe Photoshop Elements 9 after some changes on my Windows 7, 64 bit-laptop. I have read many of the forumcomments and am surprised that there seems not to exist a simple fix for this problem. To install and use a photoeditprogram should be easy and should not demand Einsteinqualities. If there is not a simple fix I will change to a Magix-software.