Hi,

I've seen the same problem posted as other sites, too, all related to non-Nikon lenses.

Borrowing a Nikon lens seems wise. If the problem resets, you likely know that the root is in 3d party connectivity, and can ferret out a solution with the lens maker.

Tokina has a solution for focus problems, maybe Sigma has a solution for this.

My best,

Mike

Giannip, if it is possible try using Nikon glass to reveal if problem is brand compability related and clean both camera and lens contacts carefully

Hi thanks the comments, all is welcomed and appreciated. Thanks for the video.
As per the video, i will not even get the single centre focus shown, nor the brackets in the top lcd panel. It all totally disappears. Are you turning adjusting the front and rear control dials? As that will change the focus points ( 9, 21, 39 etc ) when you roll your finger over them both? As well as AF-S, AF-C, AF3d etc....

Giannip said:
My New Nikon D7000, has lately been doing a few strange things. The Focus will stop working, and the enture Focus Icon with focus points, Af-a,c,s etc will totally disappear
from the top LCD panel, and also when you go into the menu all the focus modes are greyed out, not accessible. It has done this about 5 or 6 times now at random, when i turn the camera on over the last 2 weeks. I turn it on and off a couple times, or pull out the battery, and put it back in and its back to normal...Any ideas why this could be happening. I have a single sigma lens 17-50mm f2.8 EX DC OS HSM new lens. Camera is only about 7 weeks old. Should i return it....
firmware is as follows. What does A, and B and L mean?
A 1.00
B 1.00
L 1.002
Any help appreciated greatly.

I have the same problem:
http://www.youtube.com/watch?v=--E6STdFdxo

borrow, a nikon lens and give it a try.

+1 for PBPM's reply on contacts.

I have not had any problems with Nikon lenses, also remember to turn camera off when changing the lens

can't comment on third party lens as I stick with Nikon, the reason for buying Nikon cameras, for me, is the ability to use Nikons glass.

In my Canon days, I heard that sigma(and other third party lenses) sometimes had various issues being mounted on newer bodies while perfectly working with older ones. I don't know if it is true but there was a lot of speculation about this over the net. Manufacturers sometimes do offer a free of charge rechipping of firmware update for this reason.
I apologise if my post is useless.

Sounds like there could an issue with the electric contacts of the lens or the camera body. Before you worry about that though, try un-mounting and then re-mounting the lens. If that doesn't help, try cleaning the electric contacts with some rubbing alcohol.

My New Nikon D7000, has lately been doing a few strange things. The Focus will stop working, and the enture Focus Icon with focus points, Af-a,c,s etc will totally disappear
from the top LCD panel, and also when you go into the menu all the focus modes are greyed out, not accessible. It has done this about 5 or 6 times now at random, when i turn the camera on over the last 2 weeks. I turn it on and off a couple times, or pull out the battery, and put it back in and its back to normal...Any ideas why this could be happening. I have a single sigma lens 17-50mm f2.8 EX DC OS HSM new lens. Camera is only about 7 weeks old. Should i return it....
firmware is as follows. What does A, and B and L mean?
A 1.00
B 1.00
L 1.002
Any help appreciated greatly.