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What I've noticed is that when I browse from D:\Program Files\SMS_CCM\ServiceData\Messaging\OutgoingQueues That's where I get a ton of .msg files and SCCM files.
Based on my research, many situations may cause this issue. Generally speaking, the state message files are supposed to automatically copy files from the state system to MP(D:\SMS\MP\OUTBOXES\statemsg.box\folder) for every 15mintues(by default). The workflow completes after the state messages arrive at the management point are processed into .smx files by the MP Relay component. Please refer to this Microsoft article for more details.
The detailed workflow may like the image shown below:
For troubleshooting "a ton of .msg files" issue, we could check the SMSProv.log(site server side) and the ccmmessaging.log(client side) to track if there is any error during the process.
Have a good day!
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