I recently created a couple of modpacks and the first one I created works beautifully, any others I have attempted afterwards get the same error when I try to download them from the launcher, and that is that there is an error unzipping file "prequel-1.0" does not exist. The only differences between the two are the forge versions in use, the version of Minecraft, and the mods present. The working pack is for 1.8.9, whereas the non-functional pack is 1.7.10. I'm not sure what to link in order for troubleshooting. I have found nothing else on the forums that helps me.