Windows Insider chief Dona Sarkar has explained why Slow Ring insiders have been waiting so long for a 19H1 build. Despite the updates impending release in April, Microsoft hasn’t rolled out a build to slow ring users for five months. According to Sarkar, the culprit is a nasty bug.

“Many of you are asking why we haven’t released a¬†SlowRing¬†flight in a while. We have a GSOD that’s caused by a very common scenario around gaming anti-cheat codes,” she said. “Unfortunately, the fix is in the hands of our 3rd party partner company that we’re working with them on.”

Microsoft knows that many of its Slow Ring users play the game in question, so that’s the reason for the lack of release. These builds are supposed to have a higher degree of quality than the fast ring, and to ship one in this state would be unfair.

Unfortunately, there’s not a whole lot Microsoft can do until that third-party co-operates. Sarkar says that because this crash happens on all kinds of hardware it wouldn’t be possible to deliver to only unaffected users.

A Commitment to Quality

Microsoft hasn’t outright said it, but its caution in this regard is likely related to its recent commitment to Windows 10 build quality. After a buggy full Windows 10 release that deleted documents, it’s been putting more resources into maintaining stability.

Windows Slow ring insiders definitely don’t have the same requirements as a full release, but many use it as a daily driver. Keeping them happy is a win-win, as their long swathes of time spent with the OS is more likely to turn up bugs and feedback.

Unfortunately, it’s still not clear when the next 19H1 Slow Ring build will release. It depends entirely on that third-party partner, who has been pretty sluggish so far.