Possible Causes & Solutions
Locked/Corrupted PDOXUSRS.LCK file. Another network process has control of or has corrupted the main database lock file, PDOXUSRS.LCK. Close all instances of Medilink on the network, and perform a lock and net file cleanup on the server (or manually delete the *.LCK files in MEDILINK\DATA folder). If this doesn't work, use FSMGMT.MSC to remove network processes from accessing those *.LCK files, and try to delete. Last resort, reboot the server (which will very forcefully terminate access to the *.LCK files).
Locked/Corrupted INMEMxxx.REM file. Another local process has control of an INMEMxxx.REM file. Close all instances of Medilink on the local PC, and perform a lock and net file cleanup (or manually delete INMEM*.REM in %TEMP% folder). If this doesn't work, reboot the local PC and try again.
Write lock. Could be timing based because another instance has locked the table for writing. Simply retry the action again.
Variation of Server Base Directory setting. Ensure all network clients have the same exact path to the Medilink database. By default this is a UNC path like: \\<YOUR_SERVER_NAME>\MEDILINK. Avoid mapped drives or using sub folders of the Medilink share.