Trouble triyng to export With Alpha Channel in Adobe Media Encoder

[Luiz Henrique0D4D]

Hey everyone! I'm here because I'm having a big problem, and I hope someone can aid me:

I've made a video using after effects, not so complex, with just a few effects, and I'm trying to render it with the alpha channel in Adobe Media Encoder, but for some reason, the video's size becomes too big, reaching 400MB, and it's not running when I try to play it.

I've tried to render it with "QuickTime Apples 4444 Alpha", and with "QuickTime GoPro CineForm RGB 12 bits Alpha" and both end up with the same errors.

But when I render it "normally", with H264, no alpha channel, it comes out perfect, with only 6MB. And it's a video with a length of 1min only.

So, that's it, that's my problem, and I hope someone can help me, it's for a job and I need to render with the alpha channel.

Thanks in advance!