MP4 is somehow no longer usable?

[James28945572on3b]

For the last 3 years I've been doing home tour videos with a combination of Prores Raw footage from my Nikon and 4k MP4 footage from my Autel drone.  I updated Adobe yesterday from a 2022 version to the 2023 version and now my MP4's won't import and won't function in my already placed timeline.  I already created the movie and now I feel like I'm going crazy.  Everything I Google says that the MP4's were never supported, yet I've made over 100 movies using a combo of MP4 and MOV file formats.  What gives?

I can't even convert it with Media Encoder.  I'm so lost.

[Ann Bens]

Reset preferences - Premiere Help

[James28945572on3b]

That didn't help.  Reset preferences, restarted computer, still get an "unsupported codec".  I was literally editing these files yesterday and had the video working.  It wanted me to update to the latest version and now it doesn't work at all.  I'm so frustrated.  I've cleared the cache so many times.  I've rolled back my installation through every existing installation that exists and my original project file trying to be opened says "This file was made in a previous version of premiere".  They won't let me roll back earlier than 2022 so I have no idea what to do.

[Peru Bob]

my original project file trying to be opened says "This file was made in a previous version of premiere".

By @James28945572on3b

Create a new project and import the old one into it.

[James28945572on3b]

Fortunately, I can import the old project, but all the mp4 files are shown as "offline media" and a red wherever they are and then they won't import.  GPU is up to date, Premiere is up to date, and all the mp4 media plays in every video player I have on Windows (VLC, Media Player, Movies)  ...  this is crazy

[wcn_dave]

I just updated, and I can still use MP4 I have from a GoPro.  Is there any way you could share (google drive link or something) an MP4 file that you're having problems with and I can see if it works for me if you like?

[James28945572on3b]

I guess it has something to do with the Autel Evo 2's codec.  It's a 4k H265 format.  And although I have the codec on my computer (and the files play fine) and Adobe Media Encoder has it in the list and I can encode other formats into H.265, it just won't deal with it on my end as far as importing and playing it back.  And according to some other forums, Adobe is stumped too.  

[Ann Bens]

Can you upload a small file for testing?