Horizon isn't opening

so here was my situation,

I got on horizon one day and then it didn’t open, so I tried deleting it and then re downloading it. it told me I have to get this extension, okaaaaaay, but while it was downloading it changed my home screen from google to yahoo. alright I can fix that. after horizon finishes guess what? chrome blocked it. what CAN I do?

Just go to chrome://downloads and click recover file.