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Werk #18247: Certificate check: STARTTLS is now possible for SMTP

Component Checks & agents
Title Certificate check: STARTTLS is now possible for SMTP
Date Oct 7, 2025
Level Trivial Change
Class New Feature
Compatibility Compatible - no manual interaction needed
Checkmk versions & editions
2.5.0b1
Not yet released
Checkmk Raw (CRE), Checkmk Enterprise (CEE), Checkmk Cloud (CCE), Checkmk MSP (CME)

When using "Check certificates", you can now select "SMTP STARTTLS" as connection type.

This allows checking the certificate of SMTP servers that require a STARTTLS procedure to use TLS (SSL).

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