Try accessing the Management Console with another PC or terminal.
Clear the browser cache and try accessing the Management Console again.
Clear the Java cache and try accessing the Management Console again.
Try using a different browser to access the Management Console.
If all the previous steps have been checked, connect to the proxy Command Line Interface (CLI) with Secure Shell (SSH) or Serial Cable. Reset the UI with the following commands:
ProxySG#enable
ProxySG#config t
Enter configuration commands, one per line. End with CTRL-Z.
ProxySG#(config)ui
ProxySG#(config ui)reset
Resetting UI to bound system version... (this takes ~30 seconds)