1st - what version of Quicktime do you have installed?
2nd - MOV is a wrapper, what is inside YOUR wrapper - Exactly what is INSIDE the video you are editing?
Codec & Format information, with 2 links inside for you to read http://forums.adobe.com/thread/1270588
Report back with the codec details of your file, use the programs below... A screen shot works well to SHOW people what you are doing
https://forums.adobe.com/thread/1070933 for screen shot instructions
Free programs to get file information for PC/Mac http://mediaarea.net/en/MediaInfo/Download
John has just about covered all the basic questions, the prime one being "Do you have the latest version of QuickTime installed on your computer with Premiere Elements?"
If Yes. That should resolve the issue. If not, then please
1. Go to Publish+Share/Computer/QuickTime and determine if there are QuickTime presets present there.
2. Make sure that you are running the computer as Administrator since both QuickTime and Premiere Elements require that for
basic install and function.
We will be watching for your follow up.