From Newsgroup: comp.sys.ibm.ps2.hardware

POUND SIGN ("#") IN SCSI ERROR CODE

When a Diagnostic or Power-On-Self-Test SCSI error code
occurs, some SCSI hardfiles may display a pound sign ("#")
in place of the error code Drive Capacity character.
This may occur on any PC or PS/2 system which utilizes a
MicroChannel SCSI adapter or system board SCSI controller.

POST or Diagnostic error codes of the format 0210XXX# XXXX,
0210XXX#0 XXXX, or 0210XXX#1 XXXX indicate that the failing
hard disk's capacity is unspecified. In these cases, it
is necessary to check the drive for capacity.

When the drive is functioning properly, the capacity can
be obtained via the Set and View SCSI Device Configuration
screen.

The "#" should not be confused with the "U" capacity digit,
which will be displayed when a SCSI disk drive is broken and
cannot report its capacity. The "#" is only displayed when
the disk is capable of reporting it back to the system.

IBM FRUs which currently use the # capacity identifier are
p/n07H1118 (2.1GB SCSI) and p/n07H0390 (1.2GB SCSI) drives.
Future SCSI drives will also use the "#" capacity identifier
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