Description of Problem:
crash sometimes when operate on the tasks in the three level task folder

Steps to reproduce the problem:
1. create a sub task folder named "1" in "Local Folder"->"Task".
2. create a sub task folder named "2" in "Local Folder"->"Task"->"1".
3. create a new task in folder "2".
4. operate on the new created task(delete, modify,...)

Actual Results:
   crash

Expected Results:


How often does this happen? 
   sometimes

Additional Information: