Error Changing Volume Label of a Raw Disk.

[Zaaphod741]

I'm attempting to use virtualbox to create and prepare compact flash cards for use as DOS hard drives in old CNC machines. I have used the createrawvmdk function to link my physical drive to my Dos 6.22 VM, and that part seems to be working fine.. I can delete the fat32 partition, and create a FAT16 partition, format the partition, transfer the system to it, and xcopy all my files to it.. and when it's done, the drive is bootable on a DOS machine. However, when I try to automate this with my batch files that I used to use on an old DOS computer to do this, I get an error when it tries to create the volume label.

I either get "General Failure Writing Drive C" if I try using the label command to change the label, or a box in the upper left corner of my screen saying a serious disk error has occurred, and a (R) to retry, which never works, so I eventually have to just power off the machine and re-start it.

I suspect this probably has something to do with a conflict between the virtual machine any my windows 7 machine, but I'm not sure how to resolve the issue. It's a minor inconvenience as I can change the label in windows just fine, but when I have to process 20 or 30 of these, it gets to be a bit tedious to do anything manually, so I would like to get my batch files working correctly.

Any ideas??

[Zaaphod741]

An update to this... it's only drive C: that I cannot change the label of. I can change the label of any drive in the extended partition just fine.

Windows does not recognize any other partitions on these compact flash cards, probably because they are still considered removable storage.. so perhaps the fact that windows can't see the drives in the extended partition might be why I am able to modify those labels?

[Zaaphod741]

Correction... I just realized, I can't write ANYTHING to the C drive now using the virtual box DOS 6.22 guest. if I write to it with windows, I can see the files and read them with the guest, but I can't write to C. I can read and write other partitions just fine.

[Zaaphod741]

Ok, I figured this out, but there does still seem to be a bug in it. If I go to windows Disk management utility and remove the drive letter from the compact flash card BEFORE I do the fdisk, then I am able to do everything I want to the drive, Fdisk, set active partition, format, transfer system, copy files.. and it works. The file copy is 6 times slower than doing the copy with windows, but windows can only see the C: partition, I can't find any way to assign a drive letter or otherwise mount the other partitions.

Here's the bug... if I use disk management to assign a drive letter to this drive.. just look at the drive in windows, then remove the drive letter.. after that, I can NEVER write to that disk again with virtualbox unless I use fdisk to remove the partitions, and start all over.. and then, it's fine. So it's not perfect, but it is usable.