Err 01 Communications between the camera and lens is faulty. Clean the lens contacts Quick Fix - YouTube
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Any idea how to fix this? It's happening with my sigma 75-300mm lenses I haven't used it in over a year. I've cleaned it with a normal cloth by nothing is helping? :
Old Sigma 18mm lens causes Err 01 on Canon DSLR - Photography Stack Exchange
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Corrosion/damage to lens contacts, any fix? I keep getting error 01 : r/ canon
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