THIS FIELD NOTICE IS PROVIDED ON AN "AS IS" BASIS AND DOES NOT IMPLY ANY KIND OF GUARANTEE OR WARRANTY, INCLUDING THE WARRANTY OF MERCHANTABILITY. YOUR USE OF THE INFORMATION ON THE FIELD NOTICE OR MATERIALS LINKED FROM THE FIELD NOTICE IS AT YOUR OWN RISK. CISCO RESERVES THE RIGHT TO CHANGE OR UPDATE THIS FIELD NOTICE AT ANY TIME.
| Affected Software Product | Affected Release | Affected Release Number | Comments |
|---|---|---|---|
| Unity Connection | - | All releases are affected. | |
| Prime Collaboration Deployment | - | All releases are affected. | |
| Unified Communications Manager | - | All releases are affected. |
| Defect ID | Headline |
| CSCws07112 | CUC may fail to connect to Microsoft 365 SMTP server after April 30th, 2026 |
| CSCwr98478 | CUCM may fail to connect to Microsoft 365 SMTP server after April 30th, 2026 |
| CSCws04982 | PCD may fail to connect to Microsoft 365 SMTP server after April 30th, 2026 |
Cisco Unified Communications Manager (Unified CM), Cisco Prime Collaboration Deployment, and Cisco Unity Connection may fail to connect to the Microsoft 365 SMTP server after April 30, 2026.
After April 30, 2026, Microsoft will remove support for Basic Authentication with the Client Submission (SMTP AUTH) endpoints. The Microsoft 365 retiral notification of basic authentication on Microsoft 365 is available at the following link:
https://techcommunity.Microsoft 365.com/blog/exchange/exchange-online-to-retire-basic-auth-for-client-submission-smtp-auth/4114750
When SMTP interfaces are configured as a client using Basic Authentication to connect with Microsoft 365, the following may be encountered after April 30, 2026:
Workaround
Customers are encouraged to use an intermediate SMTP Relay to communicate with the Microsoft 365 SMTP server.
| Version | Description | Section | Date |
| 1.0 | Initial Release | — | 2025-DEC-08 |
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