This doesn’t appear to be one of Google’s April Fools’ jokes. YouTube’s browser checker seems to be flagging Internet Explorer 8 on Windows XP and Internet Explorer 10 on Windows 7 as unsupported.

We’ve tested this issue out on a few Windows machines and it appears that other versions of the browser that should be supported aren’t affected. Windows 8 users with IE10 can access YouTube just fine, as can IE9 users.

If you’re running IE8 on Windows XP or you’ve installed IE10 on Windows 7 in the last month or so, however, you’re probably seeing YouTube’s “Your browser is deprecated, please upgrade” page.

This is the same error that IE6 and IE7 users receive on YouTube:

Oops, your web browser is no longer supported.

YouTube works with a wide range of browsers. However, if you’d like to use many of our latest and greatest features, please upgrade to a modern, fully supported browser.

Find the latest versions of our supported browsers below.

Here is what happens when you visit YouTube.com on IE8 on Windows XP:

youtube ie8 730x323 Possible bug causes YouTube to detect IE10 on Windows 7 and IE8 as no longer supported

Here’s IE10 on Windows 7:

youtube ie10 windows7 730x426 Possible bug causes YouTube to detect IE10 on Windows 7 and IE8 as no longer supported

By contrast, here’s IE10 on Windows 8:

youtube ie10 windows8 730x216 Possible bug causes YouTube to detect IE10 on Windows 7 and IE8 as no longer supported

You will notice that I’m simply on YouTube.com, as opposed to youtube.com/supported_browsers, because I wasn’t redirected. Here’s what happens if I go to that page manually:

youtube ie10 windows 8 730x229 Possible bug causes YouTube to detect IE10 on Windows 7 and IE8 as no longer supported

The good news is that this issue can be easily circumvented by simply clicking the blue “No thanks” button or by going to YouTube.com again. Still, it’s quite misleading for users to see, especially if they’re on the latest version of Microsoft’s browser.

YouTube dropped support for IE6 back in March 2010. The company then killed support for IE7, Firefox 3.5, and Safari 3 in August 2011.

This would suggest that IE8 is next, but YouTube can’t exactly drop support for it as easily as its predecessors. That’s because IE8 is the latest version Windows XP users can install (an ancient OS millions are still using). IE9 is only for Windows Vista and Windows 7, while IE10 is only for Windows 7 and Windows 8.

Still, Google has lately been very aggressive with Microsoft. Furthermore, the company dropped IE8 support for Google Apps in November 2012.

If this were just IE8, we could potentially see this as a legitimate message, especially since it can be bypassed. Given that it shows up on IE10 on Windows 7, but not IE10 on Windows 8, we’re pretty certain this is a bug.

We have contacted Google and Microsoft about this issue.

See also – IE10 steals market share from IE9 and IE8 after landing on Windows 7; Firefox and Chrome make minor gains

Top Image Credit: Eric Piermont/Getty Images