Problem was in Windows Agent Version 12.0.3 and did not exist in previous versions.
Windows jobs systematically abort with a Return Code 9009.
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C:\>
C:\Program Files\UC4\.......\AgentWin\bin\UCXJWX6M.EXE JNR=0001124189 MNR=5000 PNR=2303 IPA=10.144.221.95 TYP=S TXT=" Job started"
'
C:\Program' is not recognized as an internal or external command,
operable program or batch file.
ATTENTION - UC4:JOBMESSENGER failed
JOB ended with RETCODE 0
JOBMSG ended with RETCODE 9009
JOB will abort with RETCODE from JOBMSG step
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