Flexis March 2026 Patch Recommendation

Applies to: Windows Server 2019 

This security update includes fixes and quality improvements that are part of the following update: 

• February 10, 2026—KB5075904 (OS Build 17763.8389) 

The following is a summary of the issues that this update addresses when you install this update. The bold text within the brackets indicates the item or area of the change we are documenting. 

• [Windows System Image Manager] This update adds a warning dialog to help users confirm that the selected catalog file comes from a trusted source. 

• [File History] Improved: File History in Control Panel when backing up files. New files with names containing some Chinese and Private Use Area characters can now be backed up. 

• [Secure Boot] With this update, Windows quality updates include additional high confidence device targeting data, increasing coverage of devices eligible to automatically receive new Secure Boot certificates. This targeting is based primarily on client device diagnostic data; due to limited data, servers are unlikely to qualify, though not explicitly excluded. Devices receive new certificates only after demonstrating sufficient successful update signals, maintaining a controlled and phased rollout 

Applies to: Windows 10 Enterprise LTSC 2019 

This security update includes fixes and quality improvements that are part of the following update: 

• February 10, 2026—KB5075904 (OS Build 17763.8389) 

The following is a summary of the issues that this update addresses when you install this update. The bold text within the brackets indicates the item or area of the change we are documenting. 

• [Windows System Image Manager] This update adds a warning dialog to help users confirm that the selected catalog file comes from a trusted source. 

• [File History] Improved: File History in Control Panel when backing up files. New files with names containing some Chinese and Private Use Area characters can now be backed up. 

• [Secure Boot] With this update, Windows quality updates include additional high confidence device targeting data, increasing coverage of devices eligible to automatically receive new Secure Boot certificates. This targeting is based primarily on client device diagnostic data; due to limited data, servers are unlikely to qualify, though not explicitly excluded. Devices receive new certificates only after demonstrating sufficient successful update signals, maintaining a controlled and phased rollout. 

Known issues in this update 

Symptoms 

After installing this update released on or after January 13, 2026, Japanese language installations of Windows Server 2019 might not correctly display Japanese characters in the PowerShell console. 

This issue is caused by an unintended change to PowerShell encoding settings, which are incorrectly set to UTF-8 following the installation of the update. English language text can appear correctly, and commands can be entered as usual. However, Japanese output text appears garbled, or with the appearance of question marks where Japanese text is intended to be shown. Japanese text which is entered into PowerShell will also be affected in the same way. 

Workaround 

There are two methods to address this issue: 

Method 1: Start PowerShell from a Command Prompt 

1. Open the Command Prompt (cmd.exe) console. To do this, you can click Start, type cmd in the Search box, and then select cmd from the results. 
2. In the Command Prompt window, type powershell.exe and then press Enter. This opens a PowerShell console where this issue does not occur. 

Method 2: Change the font in the PowerShell console 

1. Start PowerShell as usual. To do this, you can click Start, type powershell in the Search box, and then select powershell from the results. 
2. Right-click the top bar of the PowerShell console, select Properties, and then select the Font tab. Here, select MS Gothic, and then click OK.