I Can't open help file i get an error "cannot open the file ....

This error is related to windows xp,
Try the following
1.Make sure CHM File is on your hard drive,
2.Go "start" "run"
3.Type the following
regsvr32 "c:\windows\system32\hhctrl.ocx
4.Click on <enter>
5.Try to run the file again – if it doesn’t work repeat step 2 then type the following
regsvr32 c:\windows\system32\itss.dll

This will register the file on your windows system and should solve the issue