Can not delete,copy,move,file from think3Design

[irichi]

Dear all,
I have a problem to delete file that i saved from Think3 thinkDesign.
My OS was Vista,user already administrator,and the software was installed correctly.Complete scan using nod32 was no virus detected.

And this happen just for file from Think3 ThinkDesign only,the other like .doc,.xls,.jpg,.mp3 was able to delete or rename.So everytime i made a new project of design then save it, it never can be delete,move,copy,or rename.

The original OS from manufacturer is Vista,then i downgrade become XP.Unfortunately its failed,so i make a recovery and back to Vista again.

Can you tell me how to fix this problem or is there any software that i can used?
Thanks for your reply