Hi,

Looks like I already had a 'SET REPROCESS TO 1000' in there. I added the suggested 'SET REPROCESS TO 1000 SYSTEM' but it also had no effect on the error count.

On reflection I don't see why either of the above would have an effect anyway because:
(a) in my case I'm not attempting to lock anything and
(b) the default for SET REPROCESS is an indefinite wait which would be *less* likely to generate an error.

Anyway I also tried 'SET REPROCESS TO 1' and 'SET REPROCESS TO 0' - neither affected the outcome.

I looked at the IIS logs - sometimes when the 500 return code occurred the sc-win32-status was 64 ("Specified network name is no longer available", I think) but this code also appears sometimes when the sc-status was 200 so I don't suppose it's relevant....

Best
Viv