Custom Modpack "error unzipping files"

[penguin055]

So I created a mudpack and I'm really sure I've done everything correctly, but when I try to launch my mudpack, it says "error unzipping file". Is there anything I can do to fix this?

[meganerd19]

This is a rather persistent and prevalent problem I'm finding. I can't get a single downloaded modpack to work. Only the in-built ones function properly. Not a single one I've downloaded has worked.

[SpottedShadow]

I need help with this. I know I've done everything correctly, double checked it all a hundred times, and I still get this error. I know its not an issue with the launcher, as I've downloaded other packs. The problem just seems to be with this one. Can anyone help?