Thanks all, this solved my problem!

summary:
fill database
gbak database.gdb database.gbk -BA
gbak database.gbk database.gdb -C -K -R
activate indices
gfix database.gdb -mo read_only

--- In firebird-support@yahoogroups.com, "Dunbar, Norman (Capgemini)" <norman.dunbar.capgemini@...> wrote:
>
> Morning Ann,
>
> >> ..... During the restore, don't reserve
> >> space on pages ... I forget what the switch is, but the space is
> >> for back versions and a read-only database doesn't have any.
>
> That would be the -USE_[ALL_SPACE] switch.
>
>
>
> Cheers,
> Norman.
>
>
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