Unsupported File Type: when importing iPhone 6 videos

This problem is driving me nuts. I have an iPhone 6. And when I take videos on it, then go to import them into iPhoto - I regularly get "Unsupported file type" error. And then it won't let me import my videos into iPhoto. Worse yet, it makes the video inaccessible on my iPhone and is lost forever. It turns it into a Black video clip with nothing in it.

I don't understand how videos taken from my iPhone 6 can be an unsupported file type on my macbook pro mid-2012 with Yosemite 10.10.5. This happens regularly and it super frustrating because I'm losing important family videos.

Take a look at the attached screenshot for the exact error and what I'm seeing in iPhoto. Any help is appreciated.

Thanks,

Neil