How to check attachment limits in Exchange

get-transportconfig | ft maxsendsize, maxreceivesize 
get-receiveconnector | ft name, maxmessagesize 
get-sendconnector | ft name, maxmessagesize 
get-mailbox Administrator |ft Name, Maxsendsize, maxreceivesize

How to add a user to a Public Folder including all Subfolders in Exchange 2010 / 2013

Get-PublicFolder –Identity “\Public Folder” –Recurse | Add-PublicFolderClientPermission –User UserName –AccessRights PublishingAuthor


To remove a user from all public folders-

Remove-PublicFolderClientPermission -Identity "\" -User UserName