Premiere Elements 10 on what computer operating system?
I am not sure how successful you will be in resolving that issue. Always very difficult and much discussed before the Premiere Elements 13.1 Update when it was supposed to have been fixed by Adobe. I have not heard otherwise, so I am assuming the problem is gone in the latest version 14 as well.
Here is where it used to usually start
Re: I have just got this error on my Windows 8.1 PC in Adobe Premiere Elements 13:"Premiere Elements has encountered an error" --> [c:\adobe\pre\main\mediacore\mediafoundation\api\inc\Keyframe/Keyframe.h-142]
What video card/graphics card does your computer use? NVIDIA GeForce or other?
I fixed it, partly it using PERL, partly manually. The problem was in replacing '.' decimal separators by ',' made by PE10 while saving files, including backups. Curios, it did not this way later. Perhaps, this PE10 behavior was caused by its suspension, but I am wondering how it could possibly affect backups. Anyway, I solved the problem, and it did not occur anymore yet.
Thanks for the great news that you solved the keyframe h-142 error in Premiere Elements 10. It is a difficult task, and you did a great job to gain your success.
Your report of the outcome will benefit all.