If there are multiple computers on the same network using the same database, then a new version checking feature has been added to the software.  Each time a computer downloads a new version of the software that version number is inserted into the database.  All the other copies of RentMaster on the network will check if the version of the software on their computer is at least as high as that version in the database.  If it isn't, then it indicates that the computers are running different versions.  This is not a recommended configuration.  All computers should have the same version.  The version check will warn the user that errors could occur if they continue to use mismatched versions.