I've just had the same issue and i thought posting my FAHlog (pasted from Fahmon - great tool imo) could potentially be of use to others/project overall ?(despite how small a possible contribution,its the small that adds up to the whole i guess).
I'm going to try restarting the WU from the latest back up copy i made.
EDIT**Just to add my system is all stock and likely very stable wrt win smp client since i've never have any issues like this ( i can remember) since i started folding last summer (i occasionally get hanging clients assoc. the net connection (i think) but this isn't a problem with regular monitering)**
Happy New Year to all naturally
[14:08:08] Completed 550000 out of 1000000 steps (55 percent)
[14:23:49] Writing local files
[14:23:49] Completed 560000 out of 1000000 steps (56 percent)
[14:39:29] Writing local files
[14:39:29] Completed 570000 out of 1000000 steps (57 percent)
[14:51:10] Warning: long 1-4 interactions
[14:51:10] Gromacs cannot continue further.
[14:51:10] Going to send back what have done.
[14:51:10] logfile size: 353037
[14:51:10] - Writing 353573 bytes of core data to disk...
[14:51:11] ... Done.
[14:51:11] - Failed to delete work/wudata_06.arc
[14:51:11] No C.P. to delete.
[14:51:11] - Failed to delete work/wudata_06.dyn
[14:51:11] - Failed to delete work/wudata_06.chk
[14:51:11] - Failed to delete work/wudata_06.sas
[14:51:11] - Failed to delete work/wudata_06.goe
[14:51:11] - Failed to delete work/wudata_06.xvg
[14:51:11] Warning: check for stray files
[14:51:11]
[14:51:11] Folding@home Core Shutdown: EARLY_UNIT_END
[14:51:11]
[14:51:11] Folding@home Core Shutdown: EARLY_UNIT_END
[14:51:17] CoreStatus = 7B (123)
[14:51:17] Client-core communications error: ERROR 0x7b
[14:51:17] Deleting current work unit & continuing...
[14:53:21] - Preparing to get new work unit...
[14:53:21] + Attempting to get work packet
[14:53:21] - Connecting to assignment server
[14:53:22] - Successful: assigned to (171.64.65.64).
[14:53:22] + News From Folding@Home: Welcome to Folding@Home
[14:53:22] Loaded queue successfully.
[14:53:27] + Closed connections
[14:53:32]
[14:53:32] + Processing work unit
[14:53:32] Core required: FahCore_a1.exe
[14:53:32] Core found.
[14:53:32] Working on Unit 07 [January 1 14:53:32]
[14:53:32] + Working ...
[14:53:33]
[14:53:33] *------------------------------*
[14:53:33] Folding@Home Gromacs SMP Core
[14:53:33] Version 1.74 (March 10, 2007)
[14:53:33]
[14:53:33] Preparing to commence simulation
[14:53:33] - Ensuring status. Please wait.
[14:53:33] Created dyn
[14:53:33] - Files status OK
[14:53:33] this execution.
[14:53:33] - Files status OK
[14:53:34] mpressed 507.5 percent)
[14:53:34] - Starting from initial work packet
[14:53:34]
[14:53:34] Project: 2652 (Run 0, Clone 430, Gen 44)
[14:53:34]
[14:53:34] : 2652 (Run 0, Clone 430, Gen 44)
[14:53:34]
[14:53:34] ble.
[14:53:34] Entering M.D.
[14:53:51] al work pa- Starting from initial work packet
[14:53:51]
[14:53:51] Project: 2652 (Run 0, Clone 430, Gen 44)
[14:53:51]
[14:53:51] Entering M.D.
[14:53:58] rotein
[14:53:58] Writing local files
[14:53:58] cal files
[14:53:58] boost OK.
[14:53:58] Writing local files
[14:53:58] Completed 0 out of 1000000 steps (0 percent)
[15:09:39] Writing local files
[15:09:39] Completed 10000 out of 1000000 steps (1 percent)
[15:28:27] Writing local files
[15:28:27] Completed 20000 out of 1000000 steps (2 percent)
[15:49:30] Writing local files