Microsoft has released its 12th cumulative update for Windows 10 version 1511, which is the latest mainstream version of Win10 and the version you're likely running (unless you're in the Insider program). Known as KB 3156421, the update appears (type winver in the Cortana search box) as Windows Version 1511 (OS build 10586.318). I prefer to call it Win 10.1.12.
I'm very happy to report two pieces of exceedingly good news.
First: There's a detailed changelog on the official Windows 10 update history site -- a much-needed improvement that started in February, and it's still going strong. If you're curious about what's changed, that's a good place to start. The usual admonition applies:
This update includes quality improvements and security fixes. No new operating system features are being introduced in this update.
The KB article lists the security part of the patch as usual. Win10 customers will get 11 security patches covering IE (corresponds to MS16-051), Edge (MS16-052), graphics component again (MS16-055), Windows Journal again (MS16-056), Windows shell (MS16-057), Windows kernel (MS16-060) and kernel mode drivers (MS16-062), Remote Procedure Calls (MS16-061), Schannel again (MS16-064), .Net Framework again again (MS16-065), and virtual secure mode (MS16-066). In addition, I see a separate download for Adobe Flash Player (MS16-064) on my machines.
Second: "Big gun" John Wink, a Microsoft engineer, has once again offered to help any and all with installation problems. His main Reddit thread is starting to fill up. This month, Wink has separate Reddit threads for performance problems after the cumulative update, and update fails and uninstalls -- the infamous infinitely repeating spinning blue dots. I note that Reddit regular jenmsft, also a Microsoft engineer, has chimed in. With luck, she'll help out with the cumulative update, too.
Spoiler alert: For slow computers, Wink recommends that you initially disable Cortana, then report back on Reddit. For failures and uninstalls, he'd like to see your CBS log, which I describe on page 3 of yesterday's story, "20 fixes for a Windows 10 update meltdown."
I haven't yet seen invitations from Wink to kvetch on the Microsoft Answers forum or on TechNet, but they may be coming, as they did last month. Wink's already tweeted an offer to answer cumulative update questions, but Twitter's a tough place to work through a recalcitrant update.
If you have a problem with installing the cumulative update, do yourself -- and all of us -- a favor, and sound off! Get thee to Reddit and describe the problem as best you can. But please keep a civil tongue. Wink didn't cause the problems. With a little luck, he and his cohorts may well solve them.