In 7.5 it is possible to update this path in the Configuration Centre in 7.4 and previous versions there is no configuration file for Background Services, so use the following to find out which TPS url it is uring and change it if required.
The TPS url is stored as part of the services executable. To see this open up the Services console (open Start -> Run... -> services.msc) and double-click the Touchpaper Background Processing Service.
There is a read-only field called "Path to executable". Click in the text to see the flashing cursor then press the End key to jump to the far right of the text. The TPS url is at the end of the path as a command line parameter, for example:
"C:\Program Files\LANDesk\LANDesk Applications\Touchpaper.Framework.Service.exe" http://localhost/Touchpaper.Framework.Web
If you are on Service Desk version 7.2.3 or lower the quickest way to change this is to simlply uninstall and re-install the service. During the installation you are prompted to set the TPS url. If you are using 7.2.4 onwards however and have other Service Desk components installed you would need to fully uninstall them all and start the combined installer again which is most cases is not ideal. In this case the only way to change the url is to edit the services path manually in the registry.
NOTE: This change should only be made by an experienced system administrator with prior knowledge of registry editing!
Ensure the service is stopped and the Services console isn't open, then run the Registry Editor (Start -> Run... -> regedit) and navigate to:
HKEY_LOCAL_MACHINE\SYSTEM\ControlSet001\Services\Touchpaper Services Background Processing
Edit the ImagePath value to suit and then go back into the Service console. Ensure that the double quotes are kept around the path fo the executable. You should see that the "Path to executable" has changed to reflect your modification.