dfrgntfs.exe has encountered problems

I'm having problems with the system defragmentation tool dfrg.msc. When I run dfrg.msc and choose to defrag my system partition (which is an NTFS partition), a pop-up window pops right after analysing the disk. The pop message is something like this: "dfrgntfs.exe has encountered problems, we apologise for any inconveniences coursed by this..." (not for sure if this is literally correct, because I'm using a non-English XP system with SP1). Cliking OK on the pop window would close the pop-up and then in the main dfrg window there is a message like "connection to the defrag engine is lost" or something which is shown right after the system drive letter. Has anyone experienced the same problem or any clue to resolve this problem? I should add that VoptXP works OK on all my partitions including the NTFS partition. Running dfrg.msc on FAT32 partitions does not lead to any problem either.

 

boot in safe mode to defrag

 

Run chkdsk before defragmenting.