hi, i have chromebook i have installed itunes successfully but when i launch it .. it gives certificate of the server as invalid.

iTunes does not run on Chromebook. I wouldn't trust whatever download source or hack you've used. Hopefully you've been allowing your iPhone to backup to iCloud. You should be able to get a friend to help you restore it to factory settings, or take it into an Apple Store. Once it is working again you can restore from a backup if you have one.

tt2

Hello, ChromeBooks are not meant to run iTunes. That is why it is saying that.