3 weeks ago I updated my a1 body firmware from 1.32 to 1.35 and then to 2.01 as instructed by the Sony website. I then updated my 200-600mm lens from firmware version 2 to 3.

I have had the set for almost a year and was very happy with it. never had a problem.

Right after the update the problems started. The camera does not identify the lens. After powering up or waking the camera up the screen will go dark-light several times, the focus doesn't work and finally everything freezes showing F-- instead of the actual F stop. To reset the camera you have to remove the battery. It may then start normally and work for a while... until it happens again. It may happen as often as 50% of the times I turn the camera on, but not all of the time.

Before you ask... Yes I cleaned the contacts. Didn't help.

So I tried other 200-600mm lenses from friends. One lens that was updated to version 3 gave the same problems. Another lens that was not updated and in fact was still with version 1 worked fine. No problems at all.

A long chat with Sony US support resulted in... nothing. They knew nothing of the problem and only advised to send the lens to the lab. Both the a1 and the lens have already been to the lab and they found nothing. I know most people didn't encounter this problem after the update, but if you know of someone who did - I'd be very interested to hear about it.

Regards

AGZ      

This seems to be a well-documented problem that Sony have now accepted.

I went to use my A1 with the 200-600 after not using it for a couple of days and had the same issues. Lens not recognized, not focusing, etc.  I cleaned the contacts, but it didn't help.  Any solution?

My problem may be related to yours or maybe this should be a separate thread. My (used) A1 has always (1-year) had minor play in lens/mount snugness but no issues. Then, two days ago when I turned on the camera, it did not recognize the already mounted lens, did not display the F-stop and would not autofocus. The contacts look normal.  I cleaned them contacts, remounted the lens multiple times, tried my four other ff lenses (Sony 20, 90, 70-200, 200-600) but nothing changed. I also tried shifting the small play in the mount. Nothing helped yesterday but today shifting the lens reproduces the problem very clearly; a very slight turn of the lens and behavior is normal or it is not (no autofocus, no F-stop display). One time it showed the message lens is not properly attached. The looseness is not in/out but rotational and very slight, though noticeable. 

Sorry for lengthy description. Any ideas would be appreciated.

Specifically with the A1 and 200-600G it's a firmware problem. Should be fixed with v2.02:

https://www.sony.com/electronics/support/e-mount-body-ilce-1-series/ilce-1/software/00343095