From the Premiere Elements Information FAQ http://forums.adobe.com/thread/1042180
•You MUST use an account with Administrator Privileges to run Premiere Elements
•(Doing Run as Administrator http://forums.adobe.com/thread/969395 [says Encore and also for "All" versions of Premiere] will sometimes fix "odd" errors)
•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"
•Has this ever worked before? If so, do you recall any changes you made to Premiere Elements, such as adding Plug-ins, brushes, etc.? Did you make any changes to your system, such as updating hardware, printers or drivers; or installing/uninstalling any programs?
•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?
•What is your exact brand/model graphics adapter (ATI or nVidia or ???)
•What is your exact graphics adapter driver version?
•Have you gone to the vendor web site to check for a newer driver?
•For Windows, do NOT rely on Windows Update to have current driver information
•-you need to go direct to the vendor web site and check updates for yourself
•ATI Driver Autodetect http://support.amd.com/en-us/download/auto-detect-tool
•nVidia Driver Downloads http://www.nvidia.com/Download/index.aspx?lang=en-us
What computer operating system is your Premiere Elements 12 running on?
Is the problem restricted to this one movie source or to anything (including stills) that you import into the project's Timeline?
What are the properties of this movie, and what have you or the program set as the project preset to match the properties of the source media?
When you drag your movie to the Expert workspace Timeline (Video Track 1) is there an orange line over that Timeline content or no colored line?
If there is an orange line over the Timeline content and you hit the Render button above the Timeline, does the orange line turn green and the playback in the Edit area monitor become good?
When you talk about Preview Window are you referring to the Edit area monitor or the Preview Window that appears when you double click the file in Expert workspace Project Assets or the file on the Timeline?
Please give full description of the movie file involved.
We will be watching for these details so that we can customize a troubleshooting for your Premiere Elements issue.