Well the controlfile could be used unless the corrupt blocks info. is aged out & overwritten - do not remember if this is a permanent or circularly reused record in the controlfile - would expect it to be permanent - guess will have to pore deeper through the docs. - but will be obliged if you could clarify this. Will post the exact lines from the book when I can - the developer who brought this to my attention has it & have'nt been able to touch base with him yet !!