Permissions are not sticking to public folder / users not able to get in to the folder at all at times

Hi Pete,

In exchange 2013, public folder architecture uses specially designed mailboxes to store both the public folder hierarchy and the content, which is called public folder mailbox. The public folder mailbox is the same as the regular mailbox, will inherit the size limits of the mailbox database defaults when created.

We can use the following command to check the Public folder mailbox's state:

Get-Mailbox -PublicFolder "PFmailbox_name" |fl name,database,UseDatabaseQuotaDefaults 

Or check the state via EAC:

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Hope it helps,

Best Regards,

Niko Cheng
TechNet Community Support