After seeing the posts related to focus issues I fabricated a flat target from 5mm thick yellow craft foam and narrow black masking tape so I had a high contrast target. Target was set up about 10 meters from camera; camera on tripod. Using the tamron I took shots at 150 and 600mm with MFA adjustments from -10 to +10. None of the shots with the7D2 where in focus. I put the lens on my T3i and, without adjustments of course, took the same shots. Again, none were in focus. Finally I tried with my 70-300L with similar out of focus results.
Apparently I built a focus target that cameras can't focus on. Will contact USAF to see if they want to use it in their stealth technology.
Wow Rod, you gave me a nice grin to start the day. Sorry you are having trouble. It seems folks with tamrons and sigmas are unfortunately having problems. Might need the lens reprogrammed to work with the 7D2.
I have decided to return mine for an exchange do to focusing issues after trying all of the suggestions given to others and anything else my twisted mind could come up with.
Hope you can work your issue out quickly.