I came across this post while trying to troubleshoot this error myself.
This was a really stupid fix for me - I expected more from Apple but it may help others.
In the course of building a new computer (PC), I connected my phone, drivers loaded, iTunes opened and I received a message to follow the instructions on my phone. Problem was the nothing happened - phone didn't wake up, nothing on screen not even a flash. Then I received the cryptic message & started my research
WELL...had I just clicked my phone to wake it, I would have seem the "trust this computer" message...What A DUH! moment. Click yes & voila...iTunes now recognizes my phone!