USB Sticks Could Block Windows 10 Update

John Lister's picture

Microsoft has warned that having a USB device or memory card in a computer could block a major Windows 10 update. It's a simple problem that's made far worse by a resulting error message, which is incredibly confusing. The issue is likely to do with the new policy that no longer requires users to 'eject' a USB device before removing it from the system.

The problem is with computers trying to install the latest Windows 10 May 2019 Update. It's the first of the two major updates this year (and every year after) that introduces new features rather than simply fixing bugs. The "May 2019 update" refers to the complete public rollout, though some users have already started receiving the update.

Users affected by the USB problem have received a very misleading message once the system has begun the update. It starts by telling users that "The following things need your attention to continue the installation..." but then simply says "This PC can't be upgraded to Windows 10" before clarifying that the computer's hardware "isn't ready for this version of Windows 10." (Source:

Misleading Windows Update Message

It's a doubly-misleading message. Firstly, it actually refers to an update to Windows 10, rather than (as is initially implied) upgrading to Windows 10 itself. That's obviously going to be confusing to users who know they are already running Windows 10.

Secondly, the hardware not being "ready" is much less severe a problem as it appears. It's really just a glitch with the way USB sticks and memory cards work.

When users put a USB thumbstick or USB card in a computer, Windows assigns them a drive letter such as 'E' or 'F', for example, then treats the USB drives like any other hard drive attached to the system. The specific letter used may vary depending on what other devices are already attached to the computer, but the letter should remain consistent until the device is removed.

A Simple Fix

If it isn't, Windows may get confused about where to find any files on the device. Microsoft says installing the May 2019 Update could cause the assigned drive letter to change while the device is still attached. To avoid this, Windows may block the update while a device is attached.

Despite the lack of useful information in the error message, the solution is simple: just remove the USB device or memory card, then restart the update installation. Alternatively, users can hold on for a few weeks as Microsoft is planning to fix the update itself to avoid both the problem and the confusing message. (Source:

What's Your Opinion?

Should Microsoft do a better job of communicating this problem? Would it have been better to set the update to install anyway even if it might cause temporary problems accessing the USB stick or memory card? Should the update process include a checklist for users such as saving important data and removing external devices before starting?

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Dennis Faas's picture

There's always going to be glitches, unfortunately. As always, make daily / weekly disk image backups of the system in case you need to roll back to the previous version.

Boots66's picture

The only way one of my computers is on-line is by USB Wireless LAN.
Doesthis mean that I need to take down the box to a location where I would have a cable accessible to plug it in there?
Appreciate your reply Dennis.
The room where the PC lives now has no easy way to run a cable into it, so as USB LAN adapter key was the easiest way to make things happen.

Dennis Faas's picture

The article states this is an issue with USB thumbsticks / card readers. I believe it has to do with the fact that Microsoft is disabling the write cache for USB thumb sticks / card readers in this next update (as we have previously discussed). So this should NOT impact a USB wireless WiFi adapter, for example.

nate04pa's picture

I find it hard to believe that no one found this problem during pre-release testing.

buzzallnight's picture

all they have to do is leave a USB drive installed?

kitekrazy's picture

I might get some USB sticks. Sad how Windows has regressed.

bobf0648's picture

The only way I can update my little Acer Aspire E 11 is by having a sd card installed. The stupid designers didn't allow enough hard disk space for updates! (embedded Hard disk)
So I received the above error, and will have to await a MS fix. Unless someone finds one first