Some Windows 10 users have encountered an issue with Microsoft's latest round of cumulative updates for that OS, specifically with KB4494441, that is an essential update (more about that later) for all those running the October 2018 Update.

The issue here, as highlighted by folks on Reddit, is that KB4494441 is installed, and so the update is installed again by Windows 10. Update history then suggests that there are two KB4494441 updates installed, the 2nd of which includes a number two in brackets after it - KB4494441 (2).

Although this doesn't appear to make any odds and also the update is still effective all right, reported by those experiencing the issue, it has unsurprisingly resulted in some confusion about exactly what's going on with the double installation.

Microsoft hasn't replied on Reddit or elsewhere with an official explanation that we've seen, but we did just a little digging and realized that the software giant has provided further information on the Windows 10 Release Information page.

Multi-stage installation

Essentially, what's happening is that the cumulative update is actually a multi-stage procedure that requires an initial installation, followed by a reboot, along with a further installation (and another reboot).

This should just happen and be recorded because the installation of a single update, but there's an insect which is causing Windows Update to are convinced that KB4494441 has been installed twice, much more fact that isn't the situation.

There's no harm within the glitch, save for that confusion it's caused - however it could have been nice if Microsoft had provided a definite official explanation with some visibility, rather than hiding it away in the center of a convoluted Windows 10 info page.

As to the resolution from the problem, Microsoft comments: "No action is required from you. The update installation may take longer and could require several restart, but will install successfully in the end intermediate installation steps have completed.

"We will work on improving this update experience to guarantee the Update history correctly reflects installing the latest cumulative update (LCU)."

Quite simply, a fix ought to be within the pipeline to ensure that Windows Update history simply reports this cumulative update as a single entity which has been installed.

We mentioned at the outset of this story this is a vital update, and that's since it patches against what Microsoft describes like a "new subclass of speculative execution side-channel vulnerabilities" (like Meltdown and Spectre), and in addition it enables 'Retpoline' automatically.

The second is a fix made to improve performance of Spectre variant 2 mitigations, and therefore your PC (hopefully) won't be slowed up as much by said mitigations. There are generally important security and potential performance boosts within this cumulative update.