invisible MP3 files

I cannot see my mp3 files when using windows ecplorer, music match nor Studio
9.
I get these messages
" stringpak for WMesaageDialog.cpp could not be found in the string database
"
and
" LIBMGR_CANNOT_OPEN_LIBRARY_DATABASE "
this all started after I installed quicktime
I have (un)installed all a number of times, run WINDOWS XP repair
still nothing is visible.

Please, any ideas how to resolve this ? and please don't say format/install
XP...
in the meantime I have now moved all data to the secondary HDD as well as a
DVD.