You are attempting to change the client manager address for Unified Agent.
This is for the Unified Agent which works with ProxySG and ASG, not the WSS UA.
There are two methods to change the Client Manager address.
1. Use registry settings to modify "ChangeCMAllowed" value and update the Client Manager address manually (requires administrative privileges on the machine).
2. Use GPO to uninstall and reinstall UA with new client manager address.
The instructions for option 1 are below:
1. Start a registry editor application like regedit.
2. Browse to the following key: HKEY_LOCAL_MACHINE\SOFTWARE\Blue Coat Systems\Unified Agent\config
On Windows 7 (64bit), the key is located at: HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Blue Coat Systems\Unified Agent\config
3. Double-click the ChangeCMAllowed registry value.
4. In the Edit DWORD Value dialog, in the Value data field, enter 1.
5. Click OK.
6. In the UA Web browser window, click the Advanced tab.
7. In the Client Manager section, click the change link next to the current Client Manager address.
8. The Change Client Manager dialog displays.
9. In the Change Client Manager dialog, enter the following information:
a) New Address: Enter the Client Manager’s fully qualified host name or IP address.
b) New Port: Enter the Client Manager’s listen port (8084 most likely)
If software updates are ready to download at the next update interval on the new client manager and if the client is allowed to get software updates it will update to the latest version hosted on the new client manager
For option 2 see the following guide which covers using GPO for this:
Unified Agent Local Enforcement 4.10.x Deployment and Administration Guide for Windows
The uninstall and install instructions are covered In the guide. An uninstall and reinstall using GPO with large number of UA clients to work with may be more feasible than the registry option and manual change such as described in option 1.