Bought a new Summicron 35/2 for my M10 last week. After a day of shooting I recognised that it switched NOT to 'Auto lens detection'.
Instead it switched to the last Manual M setting.
And I can't set it to Auto lens detection in the menu.
It shows the correct frame lines for 35mm in the viewfinder.
Went back to the Leica store. They wanted to change the lens and ... the new lens had the same problem. They mounted my lens on their Store M 10 and Auto lens detection worked.
Have another Summilux 50mm and a Elmarit 28mm all coded and it works perfect.
Any experience with this problem someone, please?
Hans