Update: Microsoft is no longer pushing out its October update for Windows 10 as it looks into complaints of missing files after upgrading.
"We have paused the rollout of the Windows 10 October Update (version 1809) for all users we investigate isolated reports of users missing some files after updating," Microsoft states on a support page.
It's not clear what exactly is causing the problem or how widespread it is, and there is no indication of how long the update will be unavailable. In the meantime, Microsoft is asking affected users to contact the company directly if they believe files went missing after applying the update.
"If you have manually downloaded the Windows 10 October 2018 Update installation media, please don’t install it and wait until new media is available," Microsoft added.
Microsoft is rolling out its second annual Windows 10 update, known as the October 2018 Update (or Redstone 5), and some users report having trouble with it. The most egregious so far are reports of the October update deleting files.
"I have just updated my windows using the October update (10, version 1809) it deleted all my files of 23 years in amount of 220gb. This is unbelievable, I have been using Microsoft products since 1995 and nothing like that ever happened to me," a user wrote on Microsoft's support forum.
His is not an isolated incident. Other users chimed in with similar complaints, both in the forum thread and on social media, as spotted by MSPowerUser. There's also a growing Reddit thread on the topic.
As far as I can tell, my computer downloaded the latest Windows 10 update around 3pm today and during that process it unlinked my Documents directory then unpacked its own setup files that overwrote my own files.I am so angry at Microsoft right now - if this is the case.October 4, 2018
One of the suggestions raised in Microsoft's support forum is to try rolling back the update, though that doesn't appear to restore the deleted files.
The exact cause is not known. However, it appears to be an issue that also plagued preview builds in the Windows Insider program. If so, this is another bug that managed to slip through to the final release. We reported on a far less severe annoyance yesterday, that being a Task Manager bug that causes it to miscalculate CPU usage.
As always, it's recommend that you back up your files before attempting a major update. At the very least, be sure to save any mission critical documents to a non-connected drive, like a USB flash drive or external HDD. We'll let you know if this alleged bug is confirmed, and if it is, when it's fixed.