>there is help about com somewhere ???? :)

I don't know how to do this in WINDEV (maybe in its HELP there are some articles about how to create a COM server)
but in VFP you could do:

DEFINE CLASS MyCOMClass as Session OLEPUBLIC
     PROCEDURE MyTest(param1 AS String, param2 AS integer) AS String
           *** do whatever you want to do here
           RETURN [This is a test]
     ENDPROC
ENDDEFINE

Then you cold compile your EXE and when you install it on some computer you need to regiter that class so you need to run your EXE with parameter YourEXEName /regserver. Then in every other applications you could use:

oMyTest = CREATEOBJECT([YourEXEName.MyCOMClass]) && or whatever the laguage syntax for creating object is
? oMyTest.MyTest