[EXchange 2013] Can't Open to Another User Mailbox ?

Hi Everyone,

I have a problem that, When I in Administrator OWA, I want to Open Another Mailbox of any User, It can't open and have a notify error is:

X-OWA-Error: SDServerErr;Microsoft.Exchange.Data.Storage.AccessDeniedException
X-OWA-Version: 15.0.847.32
X-FEServer: EX2013
X-BEServer: ex2013.mydomain.local
Date: 1/2/1601 3:40:13 PM

Please Help me solve or guide me to fix it, thank very much