Probably 2 ways; if you're on a DOS machine, you can map a path to the executable file, and put it in Autoexec.bat (unless it's a driver, where it might go in Config.sys)
i.e - Autoexec.bat
@echo off
C:\Desqview\desqview.exe (or wherever it's stored)
etc...
The other way would be to map to where the executable file is, type it in, and press enter...
I'm trying to remember what Desqview is....hope this helps.
Pakled- missing the point, as usual.