I moved files onto an SD card in my phone, removed it, and inserted it into my computer with an SD card reader. The computer said the card could not be opened unless it was formatted, with a warning that formatting would erase all files. I canceled instead because I don't want to lose anything. If the card still works when I put it back in my phone, what is the safest way to transfer the files to my computer?
4 Answers
Yes, formatting is intended to erase the card's existing file system and can make the files inaccessible or delete them. Don't format it if you need the data. Put the card back in the phone and try transferring the files by connecting the phone directly to the computer with USB.
The computer may simply be having trouble with the card reader, the USB connection, or the phone's connection mode. When plugging in the phone, unlock it and select the USB notification for File Transfer rather than Charge Only. You can also try another cable, USB port, or card reader.
If the files become inaccessible on both the phone and computer, avoid repeated attempts to write to the card or run random recovery tools. For important data, make a full image of the card first or use a professional recovery service, since improper recovery attempts can make things worse.
Some Android phones format an SD card as adopted or internal storage. In that case, the card may be encrypted and readable only by that phone, which could explain why the computer wants to format it. If the files are visible on the phone, leave the card there and copy them over USB, Bluetooth, cloud storage, or another supported transfer method.
The phone can still open the files, so I won't format the card. I'll try transferring them directly from the phone instead.