Probleme d'export

you've tried smart rendering?  and transcoding to a different format?  and still getting the error message?  You might try creating a new sequence and copying the contents of the problematic sequence into the new sequence.  

J'ai essayer les solutions apportées mais rien ne change

thanks for the info...  Can you answer both my and Carlos' questions and suggestions in a systematic fashion.  Never easy to troubleshoot from a distance in a scattershot fashion.  Sometimes you may think that the suggestions are to complicated, time-consuming, etc.   so if you choose not to try something, let us know... But I'm great believer in workarounds...   and sometimes a successful workaround can help us find a simpler solution.

Plus précisément

Voila mon systeme

unfortunately the translate feature doesn't seem to be working as well as it should...  and my french isn't up to the challenge.  

You're having problems with hevc material?  We see reports of problems with gopro material... Have you tried "smart rendering?"

https://community.adobe.com/t5/premiere-pro-discussions/faq-what-is-smart-rendering/td-p/10648488

And always a good idea to let us know your system specs: OS version, Premiere version, amount of RAM, Hardware specs including graphics card.

You might try transcoding your hevc material to a more robust "mezzanine" format like the appropriate flavor of prores and then making the hevc material offline and then relinking to the transcoded material 

Ou puis-je trouver la séquence de formulaire des fichiers de rendu ?

try to delete render files form sequence (video previews)

make sure your sequence settings and export settings match for better results.

try to export to QuickTime GoPro Cineform YUV 10 bits, then do H.264 from that.

check if your export is using hardware or software encoding when doing H.264