---
title: "Deprecating legacy messaging protocol authentication"
canonical: "https://kb.uconn.edu/space/IKB/26063831501/Deprecating%20legacy%20messaging%20protocol%20authentication"
format: markdown
---
ITS transitioned to Modern authentication for Outlook in 2021. Modern authentication uses OAuth to provide a secure user authentication workflow, and includes support for interactive multi-factor authentication and risk analysis. The basic authentication method uses simple username and password authentication, and is vulnerable to many modern attack vectors. In an effort to keep accounts secure, Microsoft is strategically deprecating the basic authentication method on Office 365 starting on October 1, 2022. Apps that are configured to use Basic authentication will receive an HTTP 401 error: *bad username or password*. However, any app using Modern Authentication for these same protocols will be unaffected.

The following protocols that are configured to use Basic authentication will stop working unless they are transitioned to use Oauth:  


- IMAP: Outlook doesn’t support OAuth with IMAP – if you would like to use IMAP, with a client app, you’ll need another app such as [Thunderbird](https://uconn.atlassian.net/wiki/spaces/IKB/pages/26063831538). Outlook profiles that are configured to send massmails from, are required to reconfigure the clients as described here.
- POP: Outlook doesn’t support OAuth with POP – if you would like to use POP, with a client app, you’ll need another app such as [Thunderbird](#).
- ActiveSync: Native Apple mail clients in iOS 15.6 will automatically transition from Basic to Oauth a few days after the iOS 15.6 update. Android devices that are manually configured to sync emails should be removed and re-added to the device. This will automatically switch to Modern Authentication. More information can be found here.
- EWS and AuthSMTP applications : If there are applications configured to use EWS with Basic Authentication, application owners will have to modify the code to use Oauth. Many partner apps have support for Oauth and hence, the applications will require an update in the configuration or an update to the latest version.