YouTube API Won't be Accessed via Unassociated Google Account

Today, Jeff Posnick from YouTube API team notifies the YouTube API developer via Email list that YouTube API will be no longer accessed via unassociated Google Account from the end of this April.

YouTube API will gradually forbid the following four client-side login cases:

1. YouTube accounts that are not associated with any Google account.
2. Users who use OpenID, such as @yahoo.com, @aol.com, etc. to login in to YouTube API
3. Users who use two-steps-validation (Application private password is needed).
4. Usersh who are needed to input CAPTCHA.

What is YouTube API?
The YouTube APIs and Tools enable you to integrate YouTube's video content and functionality into your website, software application, or device. You 

Off topic:
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