Created attachment 11991 [details]
printlog

When I submit 2 print jobs from 2 windows command prompts from one
Client PC simultaneously, below error is logged and the data is lost
for one of the job.
(CMD prompt: copy smbprint.txt \\IPaddress\Print)
-----------------------------------------------------------------------------------------------------------
2015/12/07 22:20:39.004355,  3, pid=30819, effective(99, 99), real(99,
0)] ../source3/printing/printspoolss.c:326(print_spool_end)
  Failed to close printer Print [NT code 0x1c00001a]
-----------------------------------------------------------------------------------------------------------

This issue occurs for one out of two jobs , only when jobs are
submitted simultaneously from windows command prompts.

But if we submit jobs one after the other( 2 or 3 seconds delay) the
error won't come and no loss of data also.

I want to know why this error occurs.

As per the error code mapping it says RPC context mismatch.

I'm confused how context mismatch happened even though SMBsplclose and
SMBsplopen are having same contexts(as i can see in logs).

This can be reproduced everytime when 2 or more jobs are submitted
simultaneously without delay from windows command prompts.
(CMD prompt: copy filename \\IPaddress\Print)
open two command prompts and execute above on one and use different
filename on another one)