Subject Re: [firebird-support] After Corrupt..do gfix and Backup Restore ..stil error..
Author Lucas Franzen
Have a look at the index SUMBILL1 (and the fields and records that are
involved) and try to find out what's the real problem.
Delete the records that are causing the probem and then backup and
restore your database, but NEVER do any DML on your system tables.
This is no cure.

Can you reproduce the error after a restore on a different hard drive?
Did you check the hardware??

Luc.