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1.==>Did anything change with this new version if MEMCM?
The KB4594177 of the SCCM fixes the client notifications issue, there is no change about the third party software update.
2.Please help check the SMS_ISVUPDATES_SYNCAGENT.log on the server side to see if the third party software updates have published to WSUS. For more detailed information, please refer to this troubleshooting article:
https://patchmypc.com/troubleshooting-why-third-party-updates-dont-show-in-sccm
Note: This is non-official Microsoft article just for your reference.
Have a good day!
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