Ccleaner corrupts my bookmarks in IE7, Vista. They remain in bookmarks-list but trying to use them they crash IE7.
I took away from Ccleaner (newest 2.16.830) all internet options plus win regedit. Now bookmarks stay ok.
I have not tried what option was to blame, because corrupted bookmarks had to be deleted one by one and close down IE also.
Jaakko