Detailed Description and Symptoms
U0003590 UCUDB - DB error: 'SQLExecDirect', 'ERROR ', '42000', 'Cannot execute as the database principal because the principal 'dbo' does not exist
Investigation
This message is an error message from the MSSQL server which was passed by the ODBC interface to the Automation Engine.
The issue occurs because the dbo (database owner) is missing.
Solution
1) Check that the owner of the DB owner is the same user as the one specified in UID='username' in the [ODBC] section of UCsrv.ini.
SQLDRIVERCONNECT=ODBCVAR=SNNNNNRN,DSN=UC4PROD;UID=uc4;PWD
2) Also make sure that this user has full privileges on the Database.