Error Unzipping FIle

[Pro_Anarchist]

I need help with my modpack named MetallicPack, When i try to install it I always get the message "Error Unzipping file" , I watched a video on how to make a modpack and did everything right. Here are the steps i did

1) Made 3 folders bin, configs, and mods

2) Put mods in mods

3) Put modpack.jar in bin

4) added all three folders to archive and made it a .zip

5) uploaded it to copy.com

6) uploaded it to technic

I really need help, I have been constantly trying to make this work but this is the only problem