Are there any encrypted files on your system?
The "convert" command converts to 512 bytes clustersize,but XP needs 4 KB clustersize to handle encryption properly......
Use PM 8 or Acronis Partition Xpert to convert your filesystem.
PS:PM 8 can eventually screw up your partiton table if you forget to disable S.M.A.R.T. in your bios!
