Detect, enable, and disable SMBv1, SMBv2, and SMBv3 in Windows — by Microsoft Learn

intermediatepageLink only (©)Windows 11 24H2 and Windows Server 2025 for the SMB signing default

Microsoft's reference for checking and changing SMB protocol versions on clients and servers. It says SMBv1 has serious security flaws and is not installed by default in Windows 11 or Server 2019 and later, so old NAS boxes should be updated rather than re-enabling it. It also warns that SMB signing is required by default on Windows 11 24H2 and Server 2025, which can block connections to some third-party servers.

Quick steps

Detect: Get-WindowsOptionalFeature -Online -FeatureName SMB1Protocol
Disable: Disable-WindowsOptionalFeature -Online -FeatureName SMB1Protocol (restarts the PC)
Check server side: Get-SmbServerConfiguration | Format-List EnableSMB1Protocol

Paraphrased from the source. Menus can differ by version, so check the original for full details.

Read the full article on learn.microsoft.com

Source: Detect, enable, and disable SMBv1, SMBv2, and SMBv3 in Windows by Microsoft Learn. Licence: Link only (©).

Source reviewed: 2026-11-02
Link checked: 2026-11-02
Tested hands-on: Not by Oddbyte.Me

smb1smbnassecuritywindows

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