Firefox and eMule crash after using Defraggler

Hi, everyone!

I've got a problem after using Defraggler. I used it for the first time two weeks ago and just after it both Firefox and eMule started crashing continuously. I did everything to solve this, but nothing worked. The only solution was to format and to install Windows XP again.

Yesterday, I used Defraggler again and the problems I have explained before came back. It is very annoying that Firefox is crashing non-stop, but I have found no solution for it in any forum. May you help me, please? Anyone has had the same problem?