If you have an ActiveX Control (OCX or DLL file) that you want to use in your program, you have to register it with windows.

To register it, press on windows Start Button and choose Run...
Then in the Text Box type:    regsvr32 d:\YourDir\YourFile.Ocx
where "d:\YourDir\YourFile.Ocx" is the full path to the ActiveX control.

To unregister it, type in the text box:    regsvr32 /u d:\YourDir\YourFile.Ocx