For Vista to unistall Gimp is sufficient delete the Gimp folder in C:Program Files aand a another more hide Gimp folder in
C:/Users/ your name/.gimp
Almost the same for XP except that you should replace in that path "Users" with " Documents And Settings"
P.S: if you can't see a gimp folder in Users/yourname then you have to change options in Start/Search/Advanced Search.
Uncheck hide extension for commune file (well this may be not strictly needed but that option if checked only create troubles and no joy ) AND check " ALLOW SEARCH IN HIDDEN AND SYSTEM's FILES (as you may guess from the capital letters that may be needed)
as example because is moving from a major release to the next and then filters and script stored there will be in often incompatible and so in the best case issue a lot of disturbing warnings .
While .in the worst gimp will just abort when loading, or when try to run them
And/Or because the first install was done with a corrupted installer so may be better clean out everything
This last seems the case of those 2 messages
(or you have other theories to explain the missed unistaller ?... Very few in Windows use checksum after download to verify integrity of installer, so the case of corrupted installers is not rare).
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Sure a long answer would be better, as example i should have explained that the personal gimp folder is there to save the gimp preferences, but in case of problem save preference may also save the problem.
but in that moment i had no time for a longer reply,
cannot uninstal gimp to reinstal it
cannot uninstall gimp to reinstall it
Why should someone remove
Why should someone remove the personal Gimp folder?