Outlook 2001 for Mac

Hi Here i need lots of help.
1. We have a mac and with outlook 2001. It was configured to exchange server 5.5.
2. It was working fine. suddenly it stops working
3. I try to create a new folders named pst and pab folder.Then try to open outlook . It shows try to open the program, nothing is happening.System locks up. I need to restart the system.
4. Then I deleted complete outlook 2001 and reinstalled.
5. NOw it try to open the program, Nothing is happening. It is not even the openning the program.

Please help me resolve this problem
Thanks,
suresh