I'm working on a GPS program, and it has been working OK, but has just started producing errors in the Timer_Tick event. I can't test it on the PC, because it uses the (new) GPS driver for the built-in facility..(the rest of the program works OK, but I don't 'Open' the GPS or enable the timer on the PC) I tried copying the source to the device (and the dlls), but I get an error when loading the source: "An error occurred. An error message cannot be displayed because an optional resource assembly containig it cannot be found". Does this mean there's a chm file I also need to copy? If so, where does it need to be? Is there an equivalent to the Error object, that I can use in an Errorlabel code section, to provide more information?