In this case, the error can appear after changing the Application Panel settings. 


Example: 

  • adding your own logo, changing the color etc. 
  • then reverting the settings and clic Reset Logo. 
  • after this whenever you try to connect with the Windows client (mstsc.exe) you get an error.


Line 15961 (File "C:\Program Files (x86)\TSPlus\UserDesktop\ApplicationPanel.bin"):

Error: Variable used without being declared.




Solution :


  • open the file ApplicationPanel.ini with a notepad, located in C:\Program Files (x86)\TSplus\UserDesktop
  • delete this line: "logoffbutton=no" (or yes).




Explanation:


After changing the Application Panel settings, the server adds/changes the line "logoffbutton=no" (or yes) in ApplicationPanel.ini.