What camera (make and model)?
What operating system?
What is the exact version of Lightroom installed? Go to Help/About Photoshop Lightroom and report the exact version number.
How did you install Lightroom 3 on your new computer?
I got a new MacBook last month. I was using the same MacBook for 6.5 years with my Lightroom 3.0. I have updated it as it has prompted me. Now it's version 3.6.
I contacted Lightroom Chat & they helped me install my new serial number of Lightroom 3.6 on my new MacBook Air. After I re-opened Lightroom on my new Mac it & plugged in my Canon Rebel T3i as usual to the computer it would not come up as a source. No matter what I have tried it will not recognize my camera. I plugged my camera in & opened the photo app for Mac & it recognizes my camera right away in that app. i don't know if I need to register my camera in settings or what? It's been over 6 years so I don't remember. It's ridiculous to import them into Apple photo app, then export them to the desktop & then re-import that folder into LR. A new computer & updated LR should not be harder for importing. Any help appreciate.
Directly connecting a camera to your computer is always a risk.
Ideally you should be using a card reader.
Card readers are faster in the transfer, need no special drivers, are less error prone, and do not drain your camera battery.
I have been doing this for over 6 years. Never had an issue and I draining my battery has never been an issue. My issue is that I can't get LR to recognize my camera anymore.
I understand your issue. When cameras pretend to be hard drives, there is a risk that it will stop working for multiple reasons. This is a common problem for folks after they do software updates (OS or Lightroom).