Hi I have a problem, when I open my memory card reader, a prompt screen appears and says " disk not formatted, format it now?". I don't know what happened with my drive.I inserted the memory card into other reader and it just says the same. I tried recovery software Recuva to back-up my files. But it only said "unable to determine file system type". Did I download the wrong software or has overwriting occurred? Because I have researched that overwritten files cannot be recovered anymore. What should I do? Please help me. Thanks.

I've gotten this on memory cards and USB drives. If there is data on the disk and you can read it, then ignore the message as formatting will erase all the data. However, I would make a copy of what you need ASAP.