There is an alternative to the GUI. A set of Commands can be used from a terminal or ethernet client such as putty, realterm, or hyperterminal1). A serial client uses COM0 or COM1. An ethernet client uses ip port 49771.
After connecting you need to enter the ESC character three times. The name and version of the firmware will be displayed and a '>' command prompt. You can enter commands using upper or lower case characters.
If you connected via ethernet you will need to first enter the LOGON command. Connecting via serial does not require this.
These commands are not usually accessed directly. Instead, the GUI is a front-end to the command line and calls them. However, the IP CONFIG command may be useful to temporarily set the network parameters, so you can then use the GUI over the network.