When running Upgrade Assistant in GUI mode, you must set the DISPLAY variable properly or you may receive errors such as:
Xlib: connection to ":1.0" refused by server
Xlib: No protocol specified
Cause: These errors indicate that the DISPLAY variable is not set up properly to allow a GUI to be displayed to the screen.
Action: Set the DISPLAY environment variable to the system name or IP address of your local workstation, and re-run Upgrade Assistant.
If you continue to receive these errors after setting the DISPLAY variable, try launching another GUI tool, such as vncconfig. If you see the same errors, your DISPLAY environment variable may not be set correctly.