Had the same issue. Could not send REP or run Communication Manager. It was Kaspersky, it deleted a .dll file required to run Communications Manager. Solution as follows:

• Completely uninstalled Kaspersky
• Rebooted (Windows 10) in safe mode with networking
• Ran 2022 Web Setup, completely re-installing Lacerte
• Reboot
• Run Lacerte

Pain in the neck. And the users no longer have virus protection through Kaspersky, for which a license fee has been paid.