Hi Guys,
I made a mistake... I set the library search path accidentally to the root, and hence it is scanning my entire harddisk..

It seems that I cannot cancel it with ESC. or any other key for that matter and thus had to force it to terminate with task manager. Which luckely only resulted 5 min of work lost.
The plus side is, the program is proofing to be very stable, it was not crashing, and I did not get a "does not response" warning from windows... (which you do get from many other programs such as the adobe suite and certain autodesk programs when a user makes the same error)
O well, I learned my lesson. But it still is very silly that one cannot cancel a running task...
Any other traps or good Altium advise for a "young player"?
M.D.S