I had the exact problem - Lightroom 5.6 opens it's Import window every time I insert a memory card, even though I had UNCHECKED that option in Lightroom preferences.
HERE IS THE ANSWER
I'm running Windows 8.1, so I don't know if this applies to other Windows operating systems. This appears to be a bug in Lightroom (more on that in a minute), but it's fixed via Windows, not Lightroom. The problem lies in a Windows AutoPlay setting, not in Lightroom's preferences.
Here's how to fix it:
- Open the Windows Control Panel
- Click on Hardware and Sound
- Click on AutoPlay
- You'll see a setting for "Camera Storage." Mine was set to "Import photos (Adobe Photoshop Lightroom 5.0.64)."
- Change this setting to "Take no action."
- Click the Save button
- Exit Control Panel. Or leave it open if you want, but you won't need it again.
- Start Lightroom
Now, when you plug in a memory card, Lightroom's import window will not open.
Now, here's the bug: If you change your mind and go back into Lightroom and put a checkmark next to "show import dialog when memory card is detected," it has no effect. If you really wanted to do that, you'd have to go back to the Windows Control Panel and change the AutoPlay setting to open Lightroom. Weird!
Thank you VERY MUCH for your response.
Your suggestion worked!!!!!!
Always glad to help.