Failed to read a snapshot, because the device is not ready.

I have a continuous problem of ABR10 not being able to create a simple incremental backup of a Windows Server 2003 SBS Premium system drive. The backup job is controlled via a policy which is applied to two physical machines. The other machine (Windows Server 2003 Standard) has no problems with this policy.

I already ran CHKDSK on the SBS server, and also tried adjusting how the policy addresses which volumes are captured. Any policy changes I make continue work on the Standard server but not on the SBS server.

Both servers are exactly the same hardware and use SAS RAID arrays with three logical drives of the same size. I'm unable to tell Windows Server to handle the logical drives so as to allow for fast removal.

The ABR10 agent is Update 3 (build 10.0.12497) for Small Business Server Edition. The Standard server is ABR10 Advanced Server (same update and build).

========== Begin Log Entry ==========
Operation with partition '0-0' was terminated.
Details:
Read error.

Error code: 0x70003
Tag: 0xDF81DA2C74EC501D
Failed to read the snapshot.

Error code: 0x10C45A
Tag: 0x14181C22EF45AD6E
The device is not ready

Error code: 0xFFF0
code = 2,147,942,421 (0x80070015)
Tag: 0xBD28FDBD64EDB8BC
Additional info:
--------------------
Error code: 502
Module: 1
LineInfo: a164035b3ff39281
Fields:
Message: Operation with partition '0-0' was terminated.
Details:
Read error.

Error code: 0x70003
Tag: 0xDF81DA2C74EC501D
Failed to read the snapshot.

Error code: 0x10C45A
Tag: 0x14181C22EF45AD6E
The device is not ready

Error code: 0xFFF0
code = 2,147,942,421 (0x80070015)
Tag: 0xBD28FDBD64EDB8BC
--------------------
Error code: 3
Module: 7
LineInfo: df81da2c74ec501d
Fields:
Message: Read error
--------------------
Error code: 50266
Module: 16
LineInfo: 14181c22ef45ad6e
Fields:
Message: Failed to read the snapshot.
--------------------
Error code: 65520
Module: 0
LineInfo: bd28fdbd64edb8bc
Fields: code : 2147942421
Message: The device is not ready
--------------------
=========== End Log Entry ===========