MagicLantern software is not as good as many of us like to think. I use a Canon 5D Mark II and when I read about this software, I got excited, as probably many Canon user did, I ignored the warning on the download website that warns us - rightfully so - that the software can turn the camera into a brick. It sure did mine.
Start by removing the lens and memory card. Then test with a fully charged battery inserted. Not much else you can do. Repair cost. The charge will depend on the type and level of failure. Hopefully,. It won't be serious whatever it is.
Press the
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