Why aren't the files on my SD card showing up?

[AC Question]

I have an LG Optimus l9, and I unmounted my SD card by pressing the 'Unmount SD card" option to safely remove it. But when I put the SD card back in, all the files I had on there erased. All my music and pictures are now gone and I can't seem to find them anywhere on my phone. Please help.

 

[B. Diddy]

Welcome to Android Central! Did the card actually re-mount when you inserted it again? Go to Settings>Storage, and see if the card shows up in the External Storage section.

If the card doesn't register, tap the Mount button, if available. If nothing happens, take the card out and put it back into your computer's SD reader. Can the computer read it?