Microsoft announced plans to disable SMB1 (Server Message Block) in Windows this week. The SMB1 protocol was created in 1983 at IBM, and Microsoft began dropping support for the product in 2017 with the release of the Fall Creators Update for the company’s Windows 10 operating system.
Microsoft stopped installing the SMB1 Server service in all editions of Windows at the time, but kept the SMB1 Client service installed in Windows Home and Pro editions. Support was not dropped from these editions because Microsoft wanted users of these versions of Windows to connect to “the vast fleet of consumer and small business third-party NAS devices” which only supported SMB1.
Customers would remove SMB1 automatically after 15 days of availability if no outbound SMB1 usage was detected. Microsoft stopped installing SMB1 client support in Pro editions with the release of Windows 10 version 1809. Recent builds on the Windows Insider Dev channel also have the SMB1 client disabled in Home editions.
Although the SMB1 client is no longer installed by default, it is still part of the operating system. Older versions of Windows that have it installed will retain it after upgrades, and administrators can install the client on devices as well.
This means that there is no longer any Windows 11 Insider edition that has part of SMB1 enabled by default. In the next major release of Windows 11, this will also be the default behavior. As always, this does not affect in-place upgrades of machines where you were already using SMB1. SMB1 didn’t go away here, an administrator can still intentionally reinstall it.
Microsoft plans to remove SMB1 binaries from future versions of Windows. Windows client and server editions will no longer include required drivers or DLLs, and connections that require SMB1 will fail accordingly.
Organizations can install an “unsupported out-of-band installer package” to restore SMB1 functionality to “connect to old factory machines, medical equipment, consumer NAS, etc.”
Check, uninstall or install SMB1 now
Windows users who don’t need SMB1 may want to disable the technology if it’s still enabled on their devices.
Windows users can uninstall or install the SMB1 client as follows on their devices:
- Use the Windows-R keyboard shortcut to open the runbox.
- Type optionalfeatures and press Enter to load the “Turn Windows features on or off” configuration window.
- To uninstall SMB1, uncheck “SMB 1.0/CIFS File Sharing Support” and press OK.
- To install SMB1, check the preference and press OK.
- Windows displays a “searching for required files” window. Close once this is done.
- A restart is not necessary.
Now you: Has SMB1 been enabled or disabled on your devices?