I'm not sure what's the problem. Here's the sample code that works. You can adapt it to your requirements.

PUBLIC oForm
oForm = NEWOBJECT("form1", "fmw.fxp")
oForm.Show()
oForm.SetDayBold(DATE()- 7, .T.)
oForm.SetDayBold(DATE()-15, .T.)
oForm.SetDayBold(DATE()-23, .T.)
RETURN

DEFINE CLASS form1 AS form


	Top = 0
	Left = 0
	Height = 300
	Width = 500
	DoCreate = .T.
	Caption = "Form1"
	Name = "Form1"

	ADD OBJECT olemw AS olecontrol WITH ;
		Oleclass = "MSComCtl2.MonthView.2", ;
		Top = 6, ;
		Left = 8, ;
		Height = 270, ;
		Width = 378, ;
		Name = "oleMW"

PROCEDURE SetDayBold(tdDate, tlVal)
This.oleMW.OBJECT.DayBold(This.DateToStr(tdDate)) = tlVal
ENDPROC

PROCEDURE DateToStr(tdDate)
RETURN TRANSFORM(DTOS(tdDate), "@R 9999/99/99")
ENDPROC

ENDDEFINE

>Thanks for your help. I have tried your suggestions but with no luck. I have the olemonthcalendar inside of a container on a form. Maybe you can see what I am doing wrong.