Cin7 Core: Issue with Email-based Two factor authentication (2FA) specifically related to Microsoft email domains

Update timeline

1. investigating Apr 13, 2026, 01:50 AM UTC

   Some Core users are unable to log in via 2FA using email; please contact Support for a manual reset to use the Authenticator app instead.

2. investigating Apr 14, 2026, 08:14 AM UTC

   We are currently investigating this incident.

3. identified Apr 14, 2026, 11:13 PM UTC

   We are still working on a fix and we recommend not using @[hotmail.com](http://hotmail.com) or [live.com](http://live.com) as alternative email addresses at this time.

4. identified Apr 15, 2026, 07:39 AM UTC

   We’ve recently been advised that Microsoft has placed restrictions on our emails due to spam-related concerns. As a result, authentication and email delivery involving Microsoft domains such as [hotmail.com](http://hotmail.com), [live.com](http://live.com), [outlook.com](http://outlook.com), and variants are likely to be temporarily unreliable or blocked. We would not recommend using Microsoft 365 SSO either right now, as it could lead to ongoing login and verification issues for our users. In the meantime, we recommend either: * Using Google authenticator, Microsoft Authenticator or Authy app for login security, or * Switching to a different email domain other than Microsoft domains for your alternative email We understand this isn’t ideal, and we’re continuing to monitor and work on this to restore 2FA services to normal.

5. identified Apr 17, 2026, 08:58 AM UTC

   We’re continuing to actively work on the issue affecting email delivery and authentication for Microsoft domains (e.g. [hotmail.com](http://hotmail.com), [live.com](http://live.com), [outlook.com](http://outlook.com)). At this stage, there hasn’t been a significant change, and users may still experience issues with receiving authentication codes or using Microsoft 365 SSO. As a reminder, we recommend using an authenticator app (such as Google Authenticator, or Authy) for login security, or using a non-Microsoft email address for your alternative email where possible. We understand the ongoing impact this is having and appreciate your patience while we work towards a resolution. We’ll share further updates as soon as we have more progress.

6. identified Apr 29, 2026, 04:31 AM UTC

   We have discovered that customers are not able to send emails to Microsoft email domains e.g. outlook.com, live.com, hotmail.com, [msn.com](http://msn.com). We are working with Microsoft to resolve this.