I just added a new 70-300 Nikkor lens to my Nikkon D3000 camera. It will not auto focus or take a picture with the new lens. It seems to be installed properly and is communicating with my camera. It just does not allow me to take a picture. I can put the old 55mm lens on and it works fine. Help!
If your lens is the Nikkor AF-P 70-300mm f/4.5-5.6E ED VR lens, it is not compatible with the D3000. From Nikon's product page:
The number of cameras compatible with this lens is limited. Even for compatible cameras, a firmware update may be required. Fully compatible models: D7500, D5600, D3400, D500.
Fully compatible models (without limitations) after available firmware update: D5, D750, D610, D600, D5500, D5300, D3300. Download firmware updates at: http://downloadcenter.nikonimglib.com/en/index.html
Regardless of firmware update, these models will still have some limitations*: D4, D4S, D3, D3X, D3S, D810, D810A, D800, D800E, Df, D700, D300, D300S, D7200, D7100, D7000, D5200.
*Because these models reset focus when reverting from standby status (timer off), pre-focus shooting is not available.
Incompatible models: D2 series, D1 series, D200, D100, D90, D80, D70 series, D60, D50, D40 series, D5100, D5000, D3200, D3100, D3000, film SLR cameras.
This is true of all AF-P lenses in Nikon's lineup, the first of which was introduced in 2016. The AF-P motor system requires lens focus feedback (and possibly power delivery) that older camera body designs and/or firmware were not capable of providing.