The operating system on your microSD card can sometimes be corrupted if the Raspberry Pi is not powered down correctly. See the instruction links below for re-loading OpenELEC onto your microSD card from another computer with a card reader. Choose the link that matches the operating system for the computer you'll use to work with the microSD card:
Download the desired version of OpenELEC from the Download page, in the 'Raspberry Pi Builds' section. You'll want the 'disk image' file as shown in the example below:
For reference, the best way to power down the Raspberry Pi when running OpenELEC is;
- On the main screen, click the Power button in the lower left corner
- Select 'Power Off System'
- Wait about 10 seconds or until the green activity LED on the Pi board stops flashing
- Unplug or switch off the power supply to the Pi board