This call function can call any script/user function and also any native function. This is invented because mostly invented this clumsy work-around. For call with ByRef capability (but only with CallArgArray), see this post: Hopefully at some point AutoIt will treat AutoIt functions as-if they were user defined functions (or vice versa). Reposted this in a seperate thread for SEO mostly (<title> and <h1> matter most, after all). _CallAny("MsgBox", 0x20, "Hello, World", "