Gail you are by far my favourite superhero!

Yes I tried that initially and that didn't work and doing it since shows that a restore was interrupted and errors again.

I was trying to get online to DBCC Checkdb as this is now the second time that this has happened (to the mirror only) in a few days. I suspect there may be an issue with the IO subsystem on the mirror but need more details...which I cant get.

Thanks ever so much for the reply!