

After anchieri.8 the result is the same, my M: drive is a 1TB disk with a JFS partition
of 500GB and chkdsk run without error on it.
I think that the difference is that K: is a IOMEGA RAM drive of 160GB 
and M: is a normal external disk.  

[C:\]chkdsk K: /F
The current hard disk drive is: K:
The type of file system for the disk is JFS.
The JFS file system program has been started.
CHKDSK  Block size in bytes:  4096
CHKDSK  File system size in blocks:  39072080
CHKDSK *Phase 0 - Replay Journal Log
CHKDSK *Phase 1 - Check Blocks, Files/Directories, and Directory Entries
JFS0148: CHKDSK  Unrecoverable error reading M from K:.  CHKDSK CANNOT
CONTINUE.

JFS0187: CHKDSK  Unrecoverable error writing M to K:.  CHKDSK CANNOT CONTINUE.

    .@.......
[C:\]

for me is very important understand what mean "writing M to K:" 
is likely that writing to a RAM disk is different than writing to a normal internal disk. 




