Thank you for your post.
fmreauthenticate10 will time out after 10 minutes of non-activity. After ten minutes of non-activity, you will be prompted for the credentials.
fmreauthenticate20 will time out after 20 minutes of non-activity. Users should not have to reboot FileMaker Go.
The next time this occurs, find out what the customer was doing prior to this message. Was the customer using another application for an extended period of time? Gone to lunch? I'll need more information in order to know which direction to take this.
I have mine set to fmreauthenticate10000.. They can stay logged in all week if they want to..