From the Premiere Elements Information FAQ http://forums.adobe.com/thread/1042180
•What version of Premiere Elements? Include the minor version number (e.g., Premiere Elements 12 with the 12.0.1 update).
•What operating system? This should include specific minor version numbers, like "Mac OSX v10.6.8"---not just "Mac"
•Are you using an account with Administrator Privileges?
Run as Administrator http://forums.adobe.com/thread/969395 (Encore + "All" Premiere)
•Have you installed any recent program or OS updates? (If not, you should. They fix a lot of problems.)
•What kind(s) of image file(s)? When talking about camera raw files, include the model of camera.
•If you are getting error message(s), what is the full text of the error message(s)?
•What were you doing when the problem occurred?
•What other software are you running?
•Tell us about your computer hardware. How much RAM is installed? How much free space is on your system (C:) drive?
And some other questions...
•What are you editing, and does your video have a red line over it BEFORE you do any work?
•Which version of Quicktime do you have installed?
Please refer to your other thread on Adobe contact information for my comments on that.
It might be a good idea to contact Adobe via its Adobe Chat to discuss "Downloading, Installing, and Setting Up". This does not prohibit you from continuing your Premiere Elements 12 issues here. The positive part about the Adobe contact is that, with the latest version, it may offer the opportunity for remote troubleshooting of your computer and the issue; whereas that is not possible in this user to user forum.
Lots of avenues to pursue...the usual drill...
a. Problem antivirus and firewalls disabled?
b. Running program from User Account with Administrative Privileges as well as Run As Administrator (from right click of desktop icon and Run As Administrator selection)?
c. Latest version of QuickTime installed on computer with Premiere Elements 12?
d. Have you ever gotten the program opened long enough to update it from 12 to 12.1?
e. Video card/graphics card driver up to date according to web site of manufacturer of the card?
Please update us on your progress when you get the chance.