adding new forms

Hi all
        I'm trying to create a new form in an existing database
application. When I click on 'New form' under the file menu I get an error
dialog saying 'Unable to find both a form and a source file'
        I have previously created new forms but can't for the life of me
remember how I did it.
Can anyone help on this ??
Ted Parrett
   South Africa
   Tel: ++27 11 476 5242
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