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Table of Contents
In summary:
- PCWorld reports that Windows 11 update KB5094126 is causing severe boot failures, BitLocker recovery loops, and blue screens on business PCs.
- HP EliteBook and Dell Precision systems are particularly vulnerable due to insufficient EFI partition space for new boot components and Secure Boot certificates.
- The June update also disrupts OneDrive integration and Microsoft Word’s third-party software compatibility, despite patching 200 security vulnerabilities.
A recent Windows 11 update is causing significant problems for some users during system startup and in everyday use. As reported by Windows Latest, the June update KB5094126 (Build 26200.8655), which rolled out on June 9th 2026, is causing boot failures, blue screens, and BitLocker recovery loops on certain devices.
The update is considered important because, according to Microsoft, it patches around 200 security vulnerabilities, including several critical flaws and zero-day exploits. It also introduces new features, such as a low-latency profile and the associated performance improvements.
PCs no longer boot or end up in BitLocker Recovery
Following installation, some users report that Windows 11 no longer starts normally. Instead, they encounter blue screens or the BitLocker recovery screen, which requires entry of the recovery key. (A similar issue is also affecting some Windows 10 users, although for different reasons).
According to Windows Latest, business devices from various manufacturers, including HP and Dell, appear to be affected. Those mentioned include:
- HP EliteBook 840 G10
- HP ProBook 460 G11
- HP Engage One Pro 15.6 G2 AiO
- HP ZBook
- Dell Precision (including 7530)
In some cases, devices get stuck in a boot loop and are difficult to restore to normal operation.
Secure Boot and EFI partition
According to Windows Latest, the problem is likely related to changes in Secure Boot and the EFI system partition.
The update refreshes Secure Boot certificates and writes new boot components. On systems with very small EFI partitions (sometimes as little as 100 MB), there may not be enough free space available. Windows event logs reportedly contain TPM-WMI errors including insufficient space in the EFI partition.
HP systems may be especially vulnerable, as firmware and recovery data are sometimes stored in the EFI partition and take up further space.
In the worst cases, Secure Boot may block the system from starting, or Windows may display error code 0xc0430001 and enter BitLocker recovery.
Workaround
Affected users report that the problem can sometimes be circumvented by making a change in the BIOS:
- Have your BitLocker recovery key ready
- Open the BIOS/UEFI (on many HP devices, press Esc during startup)
- Disable Secure Boot
- Start Windows and allow the update to run through completely
- Then re-enable Secure Boot
It’s also recommended that you update the BIOS or UEFI to the latest version, as outdated firmware may also be a factor, according to the report.
OneDrive and cloud services partially disrupted
After installing KB5094126, some users report issues with OneDrive after installing KB5094126.
OneDrive may no longer open correctly from File Explorer, and access through the sidebar or system tray may become unresponsive. Clicking on the cloud storage icon sometimes produces no response.
According to Windows Latest, Dropbox and iCloud Drive have also been affected in isolated cases, though reports are far less common.
The files themselves remain accessible, for example through the direct user folder. The issue appears to affect File Explorer integration.
Word integration and desktop customizations
The update is also reported to disrupt the integration of Microsoft Word with third-party software in certain enterprise environments. This primarily affects specialized applications in the medical and accounting sectors that use Word in the background for document creation.
Word itself continues to function, but automated or embedded workflows may sometimes fail.
Microsoft has also made changes to the desktop.ini file. As a result, customized folder views or icons may no longer display correctly if the file is classified as untrusted.
Microsoft has not yet made an official statement
These issues have not yet been confirmed by Microsoft. However, according to Windows Latest, as well as reports in the Feedback Hub and on Reddit, reports from affected users are mounting.
It remains unclear when Microsoft will release a fix or an official statement.
This article originally appeared on our sister publication PC-WELT and was translated and localized from German.