Found IT
In future dont use the same names for a table, a query and a form!
You now have both a table and a form named Questionentryform
For 1 its not logical to name a table ....form
second Its not smart.. The error is popping up from your form, thus we are expecting thats where the error is. But NO... the error is in the table...
Questionno is PK, thus required but your form doesnt fill that field in the table (your combo box for questionno is unbound). Bind it and your problem is gone.
To prevent simular naming problems its smart to prefix all names
tbl before all tables
qry before all query's
etc
Regards