Further to my previous comments, I think the solution is rather simple. Just try changing the volume label (after reading it first so that it can be restored). If this succeeds, presumbly the disk is a CDRW (packet drive). Whilst looking at this problem, I also notice that GetVolumeInformation can be used to test if a drive is formatted for compression (NT/2000/XP). Perhaps, if so formatted, a warning should be given before storing zip data on it. -- James Turner www.skaro.net