Organizations (enterprise, small business, and education) with IT-managed Windows devices and updates. Note: If you are an individual who owns a personal Windows device, please go to the article Windows devices for home users, businesses, and schools with Microsoft-managed updates.

Sign-in with this account on the device registration page, then try enabling passwordless for the account. Check that your phone is not running any malware like a rootkit for example. If you are still not able to add your account, please contact Support or reach out to your IT admin.

Microsoft always keeps an eye out for unusual sign-in activity, just in case someone else is trying to get into your account. If you're travelling to a new place or using a new device, we might ask you to confirm that it really is you.

How to manage Kerberos KDC usage of RC4 for service account ticket issuance changes related to CVE-2026-20833

The cross-signing program is deprecated and new signing certificates will not be issued. Windows will continue to trust the existing binaries signed by the cross-signing program.

Scenarios that rely on Secure Boot trust (such as BitLocker hardening, boot‑level code integrity, or third‑party bootloaders and Option ROMs) may also be affected if they require updated Secure Boot trust.

Important: An improvement was included in Windows updates released on and after October 28, 2025, that refined User Account Control (UAC) prompt requirements while still addressing the security vulnerability, CVE-2025-50173. This improvement addressed an issue that created unexpected UAC prompts for some apps, including Autodesk AutoCAD. Before attempting the resolution steps included in this ...

The Microsoft Authenticator app helps you sign into your accounts when you're using two-step verification.

To make these assurances, the content creator must digitally sign the content by using a signature that satisfies the following criteria: The digital signature is valid.

To mitigate the issue, enable users to sign-in for the Microsoft Information Protection API, by doing the following: Sign in to the Entra portal, Microsoft Entra.