Error "407 Invalid COD" when installing Zello on Blackberry You need to download Zello directly from your phone’s BlackBerry browser. The file can’t be downloaded to a PC and then copied to the phone. To install the app, open http://zello.com/bb/ on your phone’s browser and choose the green Download button. Zello Support October 26, 2016 16:08 Follow Have more questions? Submit a request 0 Comments Article is closed for comments.