Fails to display occasional Olympus ORF files

From time to time my copy of FPV Pro just comes up with the question marks on an ORF file.
I wondered if it was the file so I copied the same files to my other machine and there FPV Pro can see them all.
I have re-loaded the software. It is the 64 bit version and the PC is running 64 bit Windows 7.
I have tried using F5 to refresh and that does not work.
Any clues, please?
Tony
I wondered if it was the file so I copied the same files to my other machine and there FPV Pro can see them all.
I have re-loaded the software. It is the 64 bit version and the PC is running 64 bit Windows 7.
I have tried using F5 to refresh and that does not work.
Any clues, please?
Tony