If you micro sd fails, if you're on a windows system you're SCREWED, unless you backed up the data.
However if you're on a linux system it's possible to repair micro sd using gparted.
Or if you're crazy enough, just by doing it manually thru the terminal, but if you can do it manually then you need to apply for an entry level I.T. job asap.

A quick band aid approach is to...
1. Unmount the SD
2. Format the sd with zeros.
3. Apply the MSDOS partition table.
4. Apply the FAT32 partition scheme.


Then it should work.
You're data will be completely erased however.

You can recover the data if you wipe the drive with 1's AND 0's. And using a data recovery program.
But once again if you can manage doing that, then get your butt into I.T. now!

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1998 Ford Escort ZX2 5 speed - 279,000 miles My Daily

1992 Mercedes 300D 2.5 202,000 - Pure junk
2000 Mercedes E320 Black - 136,000 miles - Needs repair

Don't forget to grease the screw and threads on the spring compressor.