Bar Refused Amanda Bynes Following DUI Arrest

Multiple sources tell us ... Bynes and some friends tried to enter the hotel bar at The Standard Hotel on Sunset Blvd. on Friday night ... but the doorman refused to let the actress inside.

We're told hotel staff members were aware Bynes had been drinking at the nightclub at The Standard on Thursday evening ... hours before her DUI arrest ... and didn't want to be associated with the actress in case she pulled a repeat performance.

Sources say Bynes and her friends left the hotel without incident.