>>This combo box is just used as a look up. The table name is kv and it only has a single field, also kv so the rowsource is kv.kv
>>
>John,
>
>Try using a rowsourcetype of Alias and make the rowsource simply Kv.

Thanks for your help Jim, the form is instantiating fine now.
I still have one other problem with these combo boxes. I have four combo boxes on this container - three of them don't respond to mouse clicks and the remaining one works fine. They are set up in the same way ie rowsource type is set to Alias and rowsource to the table name. I haven't changed any of the other settings. They all respond normally to keyboard control.
Any ideas?

John Thomason