In this case, the error description, listed under Possible Reason(s), is misleading. The real error is that the command "dos" was not found. Under Windows 95/98 or 2000, there is no command named "dos".
What do you want to do? Run a DOS command (like DIR or TYPE, etc.) or just open a DOS command prompt window?
Depending on what version of Windows you're running, to open a DOS command prompt window, use one of the following command lines with System exec.vi:
COMMAND.COM
or
CMD.EXE
and have wait until completion False.
If you want to run an internal DOS command like DIR, use one of the following command lines:
COMMAND.COM /C DIR
or
CMD.EXE /C DIR
If you set wait until completion True, the output from DIR will go to System exec.vi's string indicator labeled st
andard output.