Hi to all

I have a macro that copies a sheet and although it was working well, one day
I suddenly got the message:

A formula or sheet you want to move or copy contains the name
'HTML_Control', which already exists on the destination worksheet. Do want
to use this version of the name?
To use the name . . . . etc


If you click on 'Yes' it continues an if 'No' you can't continue although it
doesn't actually 'bomb'.

Although it still works, the user gets very confused each time it happens
(each month).

What causes it and how can I find the named 'Control' and eliminate it?
I have searched for 'HTML_Control' without success.

Thanks
Peter Bircher