If you have several servers that have been cloned or imaged they will likely have identical STA UID‘s.  Because they are all the same you will only be able to add one of the servers to the Citrix Secure Gateway STA listing.  To correct this problem and gain the ability to add all cloned servers to the STA listing follow these steps:

1. Locate the file CtxSta.config (normally under %programfiles%\Citrix\System32 on Presentation Server 4.0 or Inetpub\Scripts if IIS port sharing is used).
2. Open CtxSta.config in a text editor, such as Notepad.
3. Change the value of the UID to a unique value and save the file. It should now be possible to add multiple STAs to the Access Gateway.
4. After making the change(s), restart IIS or the XML Service as appropriate.

You should now be able to add all of the cloned servers with their new STA UID‘s to the STA listing in the Citrix Secure Gateway configuration.

http://support.citrix.com/article/CTX108361