When users leave the company, I tend to save their PST to a DVD to free up space on the Exchange server. The other day one of them needed an attachment from their mailbox, so the easiest way was to just open it from Outlook on my machine.
I copied it from the DVD to my local drive and then went to open it in outlook, but it returned the error “File access is denied”. Strange, but anyway, I changed all the file permissions and tried again, yet still I kept getting the same error. It turns out that the file was set to read only, un-ticking this stopped the error.