Exporting to mp4 ruins quality

[Mira5EC3]

Please help a student out! Finished my midterm for my adobe animate class and I want to export and post it but no matter what combination of export settings I try, the quality looks horrible instead of the clean vectors I am expecting. Stage size is 640x480 but I'm scared to change it and mess up my entire animation since it is over a minute long, includes sounds and ai files as well. A bit too complicated to export as a gif right? I downloaded Quicktime and scoured threads on this subject but it was no use. I think what is happening is that exporting changes it to a pixel file rather than the vectors it's originally made out of and that messes up the quality but I have a hard time believing there's no way around this. Please can someone help me, I feel like I've tried everything and I just want to show people my animation, I don't know why it's so hard!

[kglad]

save your fla with a version number appended.  eg, save project1.fla as project1_v000.fla.  then everytime you change something significant, increase the version number.  that way you do not have any worries about experimenting and messing up one of the fla versions.  you can always return to the original project1.fla.

[_keyframer]

Try...

1. File > Export Video
2. choose H264 as the compression type
3.  Use the drop down to select a compression based on your document type but the YouTube settings are pretty good. 
   export and let us know the results.