My SD card was removed unexpectedly and won't work anywhere no I bought a 32gb SD card for my Galaxy Mini long ago. It's never been removed from the phone. But yesterday my phone removed my SD card. I don't know why it happened. I tried to remove the SD and put it back, turn off/on phone, but nothing worked. Tried to put it in to another phone. Nothing. Then tried to put it into a laptop and it says "The request could not be performed because of an I/O device error".

Please help, it has really important files inside.
Try the following: switch off the phone, remove the card, stick it into a windows computer. It will most probably pop up a window with the message that the card is corrupt, and ask: "do you want to format it?" refuse the formatting. Open "your computer", check if the card is visible as removable medium. It likely is, even if the card is corrupt. If it is, copy the data of the card, format it (the card is corrupted after all), and copy the data back. I had that twice now.