SMB or Server Message Block is a network file sharing protocol meant for sharing files, printers, etc, between computers. There are three versions – Server Message Block (SMB) version 1 (SMBv1), SMB version 2 (SMBv2), and SMB version 3 (SMBv3). Microsoft recommends that you disable SMB1 for security reasons – and it is now more important to do so in view of the WannaCrypt or NotPetya ransomware epidemic.
Disable SMB1 on Windows 11/10
To defend yourself against WannaCrypt ransomware it is imperative that you disable SMB1 as well as install the patches released by Microsoft. Let us take a look at some of the ways to disable SMB1 on Windows 11/10/8/7.
Turn Off SMB1 via Control Panel
Open Control Panel > Programs & Features > Turn Windows features on or off. In the list of options, one option would be SMB 1.0/CIFS File Sharing Support. Uncheck the checkbox associated with it and press OK. Restart your computer.
Disable SMBv1 using Powershell
Open a PowerShell window in the administrator mode, type the following command and hit Enter to disable SMB1: If for some reason, you need to temporarily disable SMB version 2 & version 3 use this command: It is recommended to disable SMB version 1 since it is outdated and uses technology that is almost 30 years old. Says Microsoft, when you use SMB1, you lose key protections offered by later SMB protocol versions like: In case you wish to enable them later (not recommended for SMB1), the commands would be as follows: For enabling SMB1: For enabling SMB2 & SMB3:
Disable SMB1 using Windows registry
You can also tweak the Windows Registry to disable SMB1. Run regedit and navigate to the following registry key: On the right side, the DWORD SMB1 should not be present or should have a value of 0. The values for enabling and disabling it are as follows:
0 = Disabled1 = Enabled
For more options and ways to disable SMB protocols on the SMB server and the SMB client visit Microsoft. Now read: How to Disable NTLM Authentication in Windows Domain.
