Context menu in files pane causes crash

after installing version 11 (and reinstalling) every time I click the context menu on the files pane the program crashes.
I have windows 8 on 64 bit chip.
It happens only if I select a file (not a folder) and in any view-mode (details, list etc.)
it makes the program almost unusable - any advice/solution?

It is probably caused by a bad shell extension that something else has installed.

Please see Crash, exit or high CPU usage when right-clicking certain files for how to track it down.