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Display MoreIt does that because Aternos treats modpacks as server software.
Could you download your previous world,
install the modpack on your server,
then upload the world back?
You can download and upload worlds in the Worlds section.
I finally finished this and... IT WORKS! Thank you so much 
That is the mod, and not the modpack.
This is what you are looking for:
aternos.org/software/v/modpacks/curse_the-pixelmon-modpack
Yes, I tried downloading it and it erased my world, then I used back up and I went back to 8.4.0...
Aternos has updated the modpack
Tho...
I've been trying for some time to re-install Pixelmon Reforged through Technic launcher because so far I got Pixelmon Reforged from Mod List... In Aternos Mod List Pixelmon 8.4.1 isn't available so I got it as a Modpack instead from Technic Modpacks... The thing is... I have a world where I play with my friend and when I reinstall it as a Modpack the world gets erased... Then I try applying the Back Up that I made before updating the server and it goes back to 8.4.0... In short... Is there a way I can play my world with my friend with Pixelmon 8.4.1 or I have to wait till it will be added in the Mod List...? Thank you...
Hello! Very recently Pixelmon Modpack has been updated to 8.4.1! I love aternos since I can play minecraft modpacks with my friends, so can you please update it? I am so excited to try on your servers! Thank you 
Edit: Nvm, sorry to disturb you guys, I was getting Pixelmon through Forge instead of Technic this whole time, and it points out that it might be available yet at forge but it's at Technic (The launcher I use)... Sorry to disturb again.
