Verify Third-Party Library Compatibility with the New Release
If you have added any third-party (custom) jar files (for example, MySQL database driver jar files) to the old_Software AG_directory/IntegrationServer/lib/jars/custom or old_Software AG_directory/IntegrationServer/instances/instance_name/lib/jars/custom, make sure those jar files are compatible with new Integration Server or Microservices Runtime.