Upcoming Change: NTLM Removal in Git (libcurl) – Impact to Azure DevOps Server Customers

This post announces the upcoming removal of NTLM support from libcurl in September 2026, which will break Git operations over HTTPS against Azure DevOps Server for customers relying on NTLM authentication. It details how to identify NTLM usage through warnings, klist, and HTTP traces, and strongly recommends transitioning to Kerberos authentication. It also advises against NTLM fallback and suggests SSH as an alternative for workgroup environments. The post emphasizes the need for end-to-end Kerberos configuration, including SPNs and IIS settings, and provides guidance on planning for the removal of NTLM fallback.