Photoshop :: Lost File Associations - Win 7 / CS5?

Something corrupted my installation of CS5 a month or so ago after it had been working correctly and I lost all the image file associations. Photoshop worked fine but only if I directly opened files from within.  Also all the other image packages were missing from the file association list in the Windows 7 file associations tool, not just Photoshop.   Using the Windows tool to find the programmes dot exe file and create an association also locked up at the select the right package phase.
 
I have fixed this now and my reason for posting is that several previously suggested fixes in both the MS Windows fora and elsewhere on these Adobe forums were either very complicated requiring direct registry editing or didn't work.  It has taken me a while to find a work-around that worked, hence this post.
 
1) Firstly - as is stated elesewhere the obvious answer of simply reinstalling Photoshop over the existing copy doesn't work!  Unfortunately it was a while before I found this out, with several time wasting retries of this as a fix attempt.
 
2) Not saying this is guaranteed to work in every case but I ran a 3rd party free Registry Cleaner tool, this appears to have fixed the bug in the registry allowing the Windows 7 File Associations tool to work properly again.  Once that was fixed linking up each graphic type was simple.
 
Reason for posting is I wasted lots of time thinking the issue must have been a legacy from my earlier instal of a trial version of Master Suite or the older Photoshop 7 being replaced even though my CS5 edition had been working Ok for some time. because this is what is given as the usual cause.  However I think in my case it was after loading and then deleting other graphics software, possibly Real Player, which had grabbed the associations and corruped registry settings somehow at uninstall.  It appears registry cleaner restored the corruption and allowed the standard Win 7 tool to work again.