OS XP Pro SP2
IE 6

I am using CCleaner v.2.03.532
If I make an analysis in CCleaner > Registry the software finds the below 2 problems:

1. Estension not useda (Data: OpenWithList - Registry Key: HKCU\Software\Micorosoft\Windows\CurrentVersion\Explorer\FileExts\OpenWithList)
2. Problem with Open with Application (Data: C:\PROGRA..1\NewSoft\PAGEMA..1\PMVIEWER.EXE%1 - Registry Key: HKCR\PFC\shell\open

If I decide to repair the 2 problems mentioned above CCleaner repairs both successfully, in fact if I start the analysis once again the 2 problem are not found anymore by CCleaner having been them repaired successfully, but if the day after I make the analysis n the Windows Registry through CCleaner again the same 2 problems are found by CCleaner in spite of both were repaired the day before...

Any suggestion?

I am wondering whether it's normal that the 2 registry keys problems are found by CCleaner, because really they are not true problems in the registry ...
( just for info. I have Kaspersky Interner Security installed on my pc, the windows registry is new as well the OS ... )

HKCU\Software\Micorosoft\Windows\CurrentVersion\Explorer\FileExts\OpenWithList is created, when you double click a file, that has no any file extension on it (i.e. HOSTS file) and has not registered to open with any application.

Sorry for my English, but I am writing from Italy...

If I understood well that's normal that CCleaner finds the 2 problems and I should not be worry for that... the 1st problem could be that I tried to open a file with any associated file extension by default, isn't it? The 2nd problem should be a consequence of the 1st problem, is it correct?
Thanks a lot for support.
Fr@nk

Some registry issues in particular that FileExts\OpenWithList are re-occuring so no matter how much you cleanse the registry it will pop up with something else in FileExts\OpenWithList that contains useless data in it - it's completely normal, and should be expected.
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As for this it could be that you're using the program which creates the detection.
2. Problem with Open with Application (Data: C:\PROGRA..1\NewSoft\PAGEMA..1\PMVIEWER.EXE%1 - Registry Key: HKCR\PFC\shell\open

or it could be the variable after the program name that is goofed up. I'm not sure if I'm correct or not but I thought things like %1 after a program had to have a gap like this: PMVIEWER.EXE %1 or like this with quotes: PMVIEWER.EXE "%1"
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In any event there shouldn't be any harm in removing them every time they're listed in the registry cleaner.

Yes, every time you try to open file, that has no application associated with it, you get an invalid ...\Explorer\FileExts\? entry. For example, ...\Explorer\FileExts\.nfo. If you set .nfo file to open i.e. with Notepad, you won't get invalid .nfo entry anymore, when you open .nfo file.

Thank you very much indeed to CeeCee & Andavari

You're welcome.