invalid_grant error with Google Cloud Storage and Service Account

This error was due to an incorrect Service Account ID. I was using the Client ID (ending in .apps.googleusercontent.com) instead of the email address (ending in @developer.gserviceaccount.com). There is no problem with the email address.

I know this question is from a year ago.

I had this error: Error:"invalid_grant", Description:"", Uri:""

In my case, the problem was solved synchronizing the server clock with NTP. The firewall of my server was blocking a port and the server's time was not updated correctly.

For more information, visit the "Invalid Grant" section on the "Management API - Authorization" help page (relative to Google Analytics, but relevant for the error)