First of first, BEA has the worst error message ever, it just does not make any sense, maybe just for me!
When switch to a new weblogic domain, we like to copy the configuration files to the new domain in order to reserve some configurations works, such as JMS, JDBC settings.
However, you may get
weblogic.management.ManagementRuntimeException: com.rsa.jsafe.JSAFE_PaddingException: Could not perform unpadding: invalid pad byte.Does this give you any hint that your password-encrypt is incorrect?
You may need to re-encrypt your password in the new domain by using the BEA supplied weblogic.security.Encrypt tool to archive this goal.
java -cp ./weblogic/server/lib/weblogic.jar -Dweblogic.RootDirectory={your domain} weblogic.security.Encrypt {your plain text password}