HomeWinBuzzer NewsMicrosoft Confirms Windows Patch KB4535996 Is Causing PC Boot Issues

Microsoft Confirms Windows Patch KB4535996 Is Causing PC Boot Issues

Microsoft has finally acknowledged problems with Windows patch KB4535996 and says a fix is coming this month.


Last week, we reported on KB4535996, a Windows patch that was causing a series of issues for users. While the problems seemed extensive, did not acknowledge the patch was broken. That has changed and Redmond has now confirmed the issues and promised a fix.

KB4535996 was rolled out last month to solve a long-standing issue with Windows Search. While it did its job, it also caused all-new problems, something that is becoming all too familiar with Windows updates.

Users reported the Sign Tool that allows users to sign their credentials on documents was broken. Worse, many complained that the patch prevented them from booting their machines.

Complaints range from machines taking a long time to boot up to getting completely stuck in the start cycle. Luckily, users are still able to enter Safe Mode and uninstall the botched KB4535996 patch.

Microsoft says it is aware of the problems and will roll out a fix during this month.

“We're aware of issues with signtool.exe after installing the latest optional update for , version 1903 or Windows 10, version 1909 (KB4535996). If you are encountering issues or receiving errors related to signtool.exe, you can uninstall the optional update KB4535996,” the company said.

Uninstall the Update

Importantly, Microsoft has recognized the patch is causing boot problems. While there is no workaround available, the update was optional. Users who haven't yet installed it are advised to hold off until it has been fixed.

For those with the update installed who are experiencing problems, you can uninstall by following this path:

Update & Security > View update history > Uninstall updates > Select KB4535996

Luke Jones
Luke Jones
Luke has been writing about all things tech for more than five years. He is following Microsoft closely to bring you the latest news about Windows, Office, Azure, Skype, HoloLens and all the rest of their products.

Recent News