Today I have encountered a strange bug in VISTA Explorer:
Out of a sudden I was not able to multi-select files any more. I tried to neglect it but after a while, this was really driving me nuts.
A system is nearly unusable without this simple feature!
I tried reboots, uninstalled software I had installed before, but nothing helped.
Finally I decided to reset my folder settings (Organize -> Folder and Search Options -> View -> Reset Folders) and voilà after closing (do not forget to do this) the explorer window and re-opening it, the multi-select feature was there again.
So do not waste Your time in uninstalling or something else!