@Sp3ar
I tried to connect the EXO services whit PowerShell (i'm the administrator, and i have rights), i see the folder, but can't clear it. (-DeleteContet)
Also trying the MFCMapi app, (it's really cool app btw) but i needed to realise this clearing the local folders, not the server foldelrs.
I am puzzled by these above sentences: From the first sentence, I know that you want to delete those emails from Server side, it will also sync to client side. But from the seconded sentence, you said that you need to release the local folder but remain the server folder.
Here are my suggestions to delete emails:
From the client side, since you could use MFCMapi, why not open Outlook and delete emails from mailbox directly? Both of them could delete email from local cache then sync to server side.
From the Exchange online side, Search-Mailbox cannot used to delete email from a specific folder. You need to EWS to delete email from this mailbox, if your want to do that, I will help you add the dev tag on this thread.
If it doesn't work on your mailbox, could you provide more detailed information about it? It will help us to narrow down this issue.
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