If a Workstation is "offline" the other workstation can not access the check.
First check the outage of the specific workstation in the error message on the screen.
ONLY a Manager or small group of people need to have the option in Emp Class / GuestCheck Control / Override Chk Open on Offline System activated.
This needs to handled securely, because you can lose this check and use this function only if a workstation is really dead.
Override check open on offline system
Enabling this option permits an employee to pickup a check currently open on another system and to pickup a check that is owned by an offline user workstation.
NOTE: If improperly used this option may cause issues on the system. For this reason, this option should be disabled except for very specific cases, for example. a Hand Held device has been take out of range of the wireless router and no are being altered on the handheld device.