[megaloman]

Код:

@Echo Off
cls
	FOR /F "tokens=2 delims==." %%d in ('WMIC OS GET LOCALDATETIME /VALUE') DO Set "Now=%%d"
	Set /A Day=1%Now:~6,2%-100
	If %Day% EQU 15 Call :DayYes
	If Not %Day% EQU 15 Call :DayNo
Pause
Exit /B

:DayYes
	Echo DayYes
Exit /B

:DayNo
	Echo DayNo
Exit /B