Fixed. I searched all tables containing FORM_ID and found one
containing old data where FORM_ID was NOT NULL but contained 0.
Back-up and restore now works fine.

Many thanks.

> tickerboo2002 wrote:
> > Thanks for your reply. It's entirely likely that I did change a
> > column from NULL to NOT NULL using Database Workbench, but I've now
> > had the client send me their database and all columns that are marked
> > as NOT NULL contain a valid value. There are no NOT NULL columns
> > which are NULL.
> >
> > This is for my TELEPHONE_SYSTEM_ALLOCATION table, but that does not
> > contain a FORM_ID column. From the errors I listed previously, is it
> > certain that the errors are for the TELEPHONE_SYSTEM_ALLOCATION table,
> > or could it be the table following that?
>
> Yes, maybe it is the next table. Take a look in database and see which
> table is next.
>
>
> --
> Milan Babuskov
> http://www.flamerobin.org
> http://www.guacosoft.com
>