Do you still have Premiere Elements 8.0/8.0.1 installed on the same computer with Premiere Elements 12? For now I will assume that you are using Windows 7 64 bit.
It is late where I am so I will give you some things quick to try.
Right click the computer Taskbar, select Start Task Manager/Processes. In those Processes, look for any process from Premiere Elements 8.0/8.0.1 that may be opened, especially anything related to Elements Organizer 8. End Task for each of any of those processes that you find. Then try to open the Premiere Elements 12 Editor.
If that approach does not work, then delete the Adobe Premiere Elements Prefs file found in the path of
Local Disc C
and in the 12 Folder is the Adobe Premiere Elements Prefs file that you delete. If that does not work, delete the entire 12 Folder in which the Adobe Premiere Elements Prefs file exists. Be sure to be working with Folder Option Show Hidden Files, Folders, and Drives active so that you can see the complete path.
Then there is the usual drill....
a. make sure you have the latest video card driver version according to the web site of the manufacturer of the video card
b. make sure you are running the program as Run As Administrator or from a User Account with Administrative Privileges.
I do not understand the part about you not being eligible for Adobe support for your Premiere Elements 12. We can talk about that more in the morning.
Please do not hesitate to ask if you need clarification on anything written here.
Thanks for the quick suggestions. I think I found what I needed, although I'm not sure why. For anyone who might be having similar problems...
I only found one active elements 8 process (PhotoshopElementsFileAgent). I killed it, but that had no effect (which I guess I would expect).
I then ran PrE12 as the administrator, but had the same problem when I tried to launch the editor from the welcome screen. However, if I launch the editor application directy (rather than going through the welcome screen) as the administrator, it worked! This was not an ideal solution for me. I generally don't run applications with administrator privileges for security purposes, so I continued with your suggestions.
I followed the path you mentioned looking for a Prefs file, but all I found were some logs. No prefs files had apparently been created yet. What I found was that there were two folders that appeared to do the same thing (...Adobe -> Premeire Elements -> 12.0, and ...Adobe -> Premiere Elements 12.0 -> 12.0). When I deleted the 12.0 from the "Premiere Elements" folder, I could open the editor when directly launching the application. However, when I went back to the start menu, it failed again.
Then I deleted both the "12.0" and the "Premiere Elements 12.0" folders. I still could not get to the editor through the default start menu shortcut (i.e., via the welcome screen), but I can launch the editor as long as I select the application directly. I changed the target on the start menu shortcut, and now all is working fine!
So it seems that the problem is related to launching the editor indirectly through either the welcome screen or from within the organizer. Since I am using Lightroom as my catalog, I have no need for the organizer. I consider my issue solved, but this may still be an issue for others...
Thank you again for your help.
Thanks for the update and good news that you solved your problem.
For future reference with regard to the Adobe Premiere Elements Prefs file
a. You need to be working with the Folder Option "Show Hidden Files, Folders, and Drives" selected so that you can see the path.
b. As for the path, it does not include the detour to the folder named Premiere Elements 12.0. The route should be
Local Disk C
Premiere Elements (not the folder named Premiere Elements 12.0)
12.0 ( this 12 is a folder inside the Premiere Elements Folder)
and in the 12.0 Folder is the Adobe Premiere Elements Prefs file that you delete.
Please refer to the text in bold immediately above.
So, the suggest was first to delete the Adobe Premiere Elements Prefs file and see what happens.
If that did not work, the next suggestion was to delete the whole Premiere Elements Folder in which the Adobe Premiere Elements Prefs file exists.
It sounds like you have everything worked out so the above may just be information for future reference if and when needed.