When you have a window open in MS Dynamics GP you can hit F1 for help on that window. There is no error and nothing happens.
Locate the dex.ini file. Usually in C:\program files\microsoft dynamics\gp\data.
Right click on the file and edit. If these two lines do not exist add them and save.
DexHelpPath=C:\Program Files\Microsoft Dynamics\GP\
DexHelpPath=C:\Program Files (x86)\Microsoft Dynamics\GP\