Sign-in & Login Problems

Fix Microsoft Entra ID Sign-In Error 50053 for SMTP Devices

Maira Mehtab Sep 27, 2026 869 views

Question details

Users need to resolve an intermittent sign-in error 50053 that occurs when printers or other hardware devices attempt to authenticate via SMTP using Microsoft Entra ID.

Product: Microsoft Entra ID
Device & OS: not provided
Scenario: Configuring network printers or secondary devices to send emails using a user account for SMTP authentication.
Observed behavior: The SMTP authentication fails intermittently, returning Microsoft Entra ID sign-in error code 50053.

Before you start

Ensure you have administrative access to your Microsoft Entra ID (formerly Azure AD) portal and verify that your printer or device firmware is up to date before modifying authentication policies.

Solution 1Recommended

Review Entra ID Sign-In Logs and Verify Security Policies

Investigate the root cause of the error by checking the authentication logs and ensuring that security policies allow SMTP authentication for the specific account.

Error 50053 typically indicates that a sign-in attempt was blocked. This often happens if the account is locked due to too many failed attempts, or if Conditional Access policies are blocking legacy authentication methods like SMTP.

Access Sign-In Logs

Log in to the Microsoft Entra admin center as an administrator and navigate to 'Identity' > 'Monitoring & health' > 'Sign-in logs'.

Identify the Blocked Request

Filter the logs by the affected user account and look for the failed sign-in events displaying error code 50053 to see the exact reason for the block.

Update Device Credentials

Log into the web interface of your printer or SMTP device and verify that the stored email address and password are correct and up-to-date.

Check Authentication Methods

Ensure that 'Authenticated SMTP' is enabled for the specific mailbox in the Microsoft 365 Admin Center, and verify that your Conditional Access policies do not unintentionally block legacy authentication for this device's IP address.

Basic Authentication Deprecation: Microsoft has deprecated Basic Authentication for most protocols. Ensure your SMTP configuration adheres to current Microsoft guidelines for SMTP AUTH.

Solution 2

Contact Microsoft Q&A and Support

If the error persists after verifying credentials and policies, escalate the issue to Azure and Entra ID specialists.

Free Microsoft Office alternative

Discover WPS Office for Your Daily Document Needs

While troubleshooting complex Microsoft Entra ID network configurations, you might also be looking for a reliable, hassle-free document suite for your local tasks. WPS Office is a lightweight, free alternative to Microsoft Office that offers excellent compatibility and a seamless offline experience without the need for constant cloud authentication.

1. Download the Installer: Visit the official WPS Office website and click the Free Download button.
2. Install the Software: Run the downloaded setup file and follow the simple on-screen instructions.
3. Start Creating: Open WPS Office and instantly begin editing your documents, spreadsheets, and presentations.

Highly compatible with Microsoft Word, Excel, and PowerPoint file formats.No complex cloud authentication required for offline document editing.Lightweight application that installs quickly on both newer and older devices.Features a familiar user interface to ensure a zero learning curve for new users.

microsoft office alternative - wps office

Frequently Asked Questions

What does error code 50053 mean in Microsoft Entra ID?

Error 50053 indicates that an account is locked because the user tried to sign in too many times with an incorrect user ID or password. It is a security measure to prevent brute-force attacks.

Why is my printer failing to authenticate via SMTP in Microsoft 365?

The printer might be using outdated credentials, SMTP AUTH might be disabled for that specific mailbox, or your organization's Conditional Access policies are blocking legacy authentication from the printer's location.

How do I check if Authenticated SMTP is enabled for a user?

In the Microsoft 365 admin center, go to 'Active users', select the specific user account, click the 'Mail' tab, select 'Manage email apps', and ensure the 'Authenticated SMTP' box is checked.

Login & Account Issues