msacal70.ocx is a calendar control from Office 97 or maybe Access 97. mscal.ocx is the Calendar Control 9.0 that came on our Win2000 boxes. If your running on a system with the new Windows Installer technology, you MAY have problems if you add the ActiveX control to your ActiveX toolbar. The only way I was able to get the control to work on Win2000 was as follows:

thisform.Addobject("myCal",'OLEControl','MACAL.Calendar.7')
with this form.myCal
.left = 10
.top = 10
.height = 200
.width = 350
.visible = .T. && Critical
endwith

I needed some code for several methods, so I needed to add a procedure file to get this funtionality.

If you work in a development environment where some boxes are Win9x and some are WinNT, there is a hard coded reference to either x:\Windows\System\xxxx.ocx or x:\WINNT\System32\xxxx.ocx. So on the other boxes, you get an OLE error when you try to modify the form.

Wish I could take credit for this tip, but Ceil Silver on CIS help me work this out.