TypeError: Mscrm.Form_onsave is not a function

   at eval (eval at RunHandlerInternal (crmpg-test.harriscomputer.com/.../ClientApiWrapper.aspx), <anonymous>:1:7)

   at RunHandlerInternal (crmpg-test.harriscomputer.com/.../ClientApiWrapper.aspx)

   at RunHandlers (crmpg-test.harriscomputer.com/.../ClientApiWrapper.aspx)

   at ExecuteHandler (crmpg-test.harriscomputer.com/.../ClientApiWrapper.aspx)

   at Mscrm.TurboForm.Control.CustomScriptsManager.$Cb_1 (crmpg-test.harriscomputer.com/.../formcontrols.js)

   at Mscrm.TurboForm.Control.CustomScriptsManager.executeHandler (crmpg-test.harriscomputer.com/.../formcontrols.js)

   at Mscrm.TurboForm.Control.CustomScriptsManager.executeHandlerByDescriptor (crmpg-test.harriscomputer.com/.../formcontrols.js)

   at crmpg-test.harriscomputer.com/.../formcontrols.js

   at crmpg-test.harriscomputer.com/.../global.ashx

   at Mscrm.TurboForm.Control.Data.DataEntity.$Dd_1 (crmpg-test.harriscomputer.com/.../formcontrols.js)

We are using CRM 8.2 on-premise.