When using long filenames, you need to wrap the path in quotes. Try:
SET DEFAULT TO "&gcPath"

>Hi all,
>
>I have a program where I use the following code to finde the default path of the program:
>
>m.home = SYS(16)&& save executing program file name
>IF !glDebug
> pos = AT(UPPER('\MyProgram.exe'), UPPER(m.home), 1)
>ELSE
> pos = AT(UPPER('\progs\MyProgram.fxp'), UPPER(m.home), 1)
>ENDIF
>m.home = SUBSTR(UPPER(m.home), 1, pos)
>RELEASE pos
>gcPath = m.home
>
>SET DEFAULT TO &gcPath && Line the error occurs at
>
>As long as the program is located in the C:\MyProgram\, no problem. As soon as I move the program to let's say C:\Program files\MyProgram\, I get an "Invalid Path Name" error. If I choose "Ignore", the utility runs properly.
>
>What could be causing this???
>
>TIA