Google blocked the YouTube app for Windows Phone from accessing video today, claiming it violates terms of service. Windows Phone

Google has blocked Windows Phone users from accessing YouTube because, it says, Microsoft’s app violated its terms of service. A previous version of the YouTube app for Windows Phone developed and released by Microsoft on May 7 did not display advertisements. YouTube, a Google company, requested that Microsoft remove the app from its Windows Phone Store and disable existing installations.

Google warned that it would block the Windows Phone app in May

Microsoft claimed in a statement at the time that “Google has refused to work with us to develop an app on par with other platforms.” Google gave a one-week deadline for Microsoft to change the app to operate under the YouTube terms of service. Microsoft responded by changing their version of the app on May 22, issuing a statement that they had “updated the Windows Phone YouTube app to address the restricted video and offline video access concerns voiced by Google.”

Two days later, on May 24, Google and Microsoft issued a joint statement that said they were “working together to update the … app to enable compliance with YouTube’s API terms of service, including enabling ads, in the coming weeks.”

On Tuesday, Microsoft released a new YouTube at that the company said addressed “the concerns Google expressed in May.” In addition to displaying advertisements, the new version of the YouTube app for Windows Phone included the ability to upload videos to the service. Today, the app was blocked from streaming content by YouTube, who said in a statement that “Microsoft has not made the browser upgrades necessary to enable a fully-featured YouTube experience, and has instead re-released a YouTube app that violates our Terms of Service.”

Microsoft claims Google is imposing unfair restrictions

Microsoft’s legal counsel today claimed that Google is unfairly imposing a restriction on Windows Phone that it does not require for Android or iOS -- a YouTube app based on the HTML5 programming language. Microsoft claims that the two companies decided that building a new YouTube app for Windows Phone in the new programming language would be too time-consuming, difficult and costly.

“We have always had one goal: to provide our users a YouTube experience on Windows Phone that’s on par with the YouTube experience available to Android and iPhone users,” Microsoft Deputy General Counsel David Howard wrote in a blog post. “Google’s objections to our app are not only inconsistent with Google’s own commitment of openness, but also involve requirements for a Windows Phone app that it doesn’t impose on its own platform or Apple’s.”

Google did not immediately respond to a request for comment. Google develops the Android operating system (OS), which tops Apple’s iOS as the most popular smartphone OS in the world.

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