From what I have just read about NVENC H264, this should not be supported by Premiere Elements. Premium Elements does not support CUDA. You are thinking Premiere Pro on this one.
What version of Premiere Elements do you have or thinking about getting...what computer operating system.
Please review the September 2014 statement of Adobe's PRE_help when referring to Premiere Elements 13 and CUDA and related matters.
Premiere Elements 13 does not support CUDA.
We do support Intel based hardware acceleration on 64-bit Windows installations. If you have the Intel HD Graphics display adaptor, look for the version number. If it is Intel HD Graphics 2xxx, or above (3xxx, 4xxx, 5xxx), the following features are accelerated
2. Publish/Share (MPEG and AVC presets)
This is governed by a setting in preferences (Edit -> Preferences -> General -> Use Hardware Acceleration... checkbox). It is turned ON by default.
This is only for the mentioned Intel hardware. Even if you have a nVidia/ATI display adaptor that is generally considered "more powerful", the feature will not work unless the supported Intel dsplay adaptor is available.
Premiere Elements Team
If you want to salvage any problem video, you could explore taking the problem video into the free HandBrake to obtain the H.264.mp4 version of it.
And, then import that H.264.mp4 version into the Premiere Elements version.
Please review and consider the above details to determine if I have interpreted your question as you meant it to be.
Yeah I found HandBrake after I posted this and that seemed to correct the issue. Thanks for the reply. I have Windows 7, Premiere Elements 12.1.
Great news. Great job.
Glad that HandBrake gave you the H.264.mp4 version which you could import and use successfully in your Premiere Elements project.
Thanks for letting us know the outcome.