Thanks Paul, John and Erik,
Searching the registry I found that in fact one ocx and one dll exist(mapobjects.ocx, moplus.dll). All objects, except four including the problematic one, were in ocx. Now I changed the syntax to createobject("moplus.grouprenderer") and all is working fine.
Thanks again for your precious help.
Cetin

>1. Register the ocx file on one computer.
>2. Open the registry database (using regedit.exe)
>3. Search for the name of the ocx file.
>
>You should find all the controls/classes exposed by that ocx. If a class is not registered, you cannot instantiate it from VFP.
>
>Vlad
>
>>I have an activex control that contains about 30 other objects. One of them should be "GroupRenderer" but whenever I try to createobject() it, I get class definition ... not found. How could I check if its name is misspelled in help file. MTIA.
>>Cetin