ScrewDrivers is a print driver utility, and must be removed when clients are not connected to the Server. You do not need to use Install Mode because ScrewDrivers is an MSI, and does not cache data during install or uninstalls. Follow these directions to ensure ScrewDrivers is upgraded properly: 

1. Connect to the Server at the console. If you are remote use mstsc.exe /console.
2. Verify all remote sessions are closed. Connections can be managed in the Users tab of tsadmin.exe and taskmgr.exe.
3. Verify there are no ScrewDrivers printers on the server. In Printers and Faxes audit the printer 'Model', and delete any printer using ScrewDriver4. If you cannot delete a specific printer then stop the Print Spool service, delete all files from the Print Spool directory, and start the Print Spool service.. The default directory for the Spooling is Windows\System32\Spool\Printers. If you cannot delete all ScrewDrivers printers then you MUST restart the server after uninstalling ScrewDrivers.
4. Access Add or Remove Programs, and remove ScrewDrivers Server v4.
5. Install the new version of ScrewDrivers Server.
6. Test and verify the new version of ScrewDrivers works.