My Nikon D80 keeps blinking error where the iso should be

It blinks "Err" where the iso should be(the iso auto also blinks above the battery icon), and i can take pictures but they don't show up on the playback screen, instead it says "folder contains no images".It won't let me pop the flash up, and when i put it in auto focus it doesn't move at all. Also when i take a picture the aperture shows for like a second.
I have a Tamron AF 28-80mm lens on it. I've taken the lens off, blew inside trying to get any dust out, That didn't work
I have a 16 GB digitalfim SD memory Card. I tried formatting it, that didn't work. I put my memory card in my friends canon and it worked fine.
I'm still leaning towards there something being wrong with the lens, but i need a second opinion and some other tips on how to fix it on my own.

Look on page 132 of your user manual.

The first question is does this only happen with the third-party lens or all of them including Nikkor lenses?

Dust will not cause such a problem

Does your D80 support memory cards larger than 2 gb?

Call Nikon and ask them to help you troubleshoot the problem

Make sure the aperture ring of the lens is set on f32 or even just beyond that.

I have a problem when I switch on my Nikon D80. On the LCD "Err" is flashing. The Flash doesn't pop up. The AF Doesn't work. The DoF preview doesn't work. But the shutter works, but no images are stored.