Symptoms
When attempting to unarchive an employee, an error occurs: "The unarchive failed. This is most likely because there are not enough employee or manager licenses left. Check the log file for more detail."
However, there is an available employee or manager license (verified in Help menu, About).
The wasptime5.log file shows this error: "Exception UnArchiving employee: Value was either too large or too small for an Int32."
Cause
The Employee ID of the employee you're trying to unarchive is the same as another Employee ID. This happens when the user sets the Employee ID of a new employee to the same Employee ID of an Archived user. (Note: WaspTime will refuse to allow reuse of an Employee ID of an Active or Inactive user.)
Resolution
Edit the Employee ID so that it is unique in the system. The error will no longer occur.