This was after our upgrade again. It doesn’t stop it from posting or saving just throw the error a bunch of times.
Check any customizations and personalizations. There may be fields with new GUIDs. You can purge personalization for a user and if that works, then do it for the rest of the users of this command. System Management | Upgrade/Mass Regeneration | Customization Maintenance
Mark W.
We deleted all our personalizations during the upgrade not to run into problems.
Upgraded to 600.4 last night issue was resolved.