I have a 28Gb backup file from a production server, copied to the mirror server. The database itself is 125Gb.
I have copied this same file to a Dev server and restored without problems.
On the mirror server I get the red 'X' and the tooltip states 'Could not retrieve information from the server about <filename>'
I set the permissions on the file, folder and parents to 'Everyone, Full Control' and nothing has changed. I've restarted SQLB as well.
It takes several hours to copy this file, so I don't want to have to do it again.
We're on a 14-day trial of SQLB, but if I can't use it then I don't see the point in purchasing it.