For years we have been saying how running security software that does any monitoring (active/passive) or inspection of Exchange processes/file paths (such as Anti-Virus, for example) on your Exchange...
Updated Jan 12, 2024
Version 5.0
Blog Post
LukasSMSFT
Microsoft
MicrosoftTechresolve the AV exclusions (full list here: https://aka.ms/ExchangeAV) should be set regardless of if you're running Microsoft Defender or any other AV solution.
We've tested that Exchange Server 2019 runs fine even if the exclusions mentioned in this blog post are removed. However, we've tested this with Microsoft Defender only (not with any other AV solution) and therefore recommend putting the exclusion back if you experience any performance or other issue (and report the issue to us).