max user limit

Hi, I have a computer that holds documents that users access. There are only 7 users that access this share. Sometimes if a user tries to access a file on this share an error comes up that user limit as been reached. I know that this can’t be because user limit is set to max, which is 10 users on the shared drive. I have to log off then back on the shared drives computer, then it will be OK for awhile. Has anyone seen this before? Thanks