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Werk #20010: Certificate check: STARTTLS is now possible for IMAP

Component Checks & agents
Title Certificate check: STARTTLS is now possible for IMAP
Date Jun 2, 2026
Level Trivial Change
Class New Feature
Compatibility Compatible - no manual interaction needed
Checkmk versions & editions
3.0.0b1
Not yet released
Checkmk Community, Checkmk Pro, Checkmk Ultimate, Checkmk Cloud, Checkmk Ultimate MT
2.5.0p6 Checkmk Community, Checkmk Pro, Checkmk Ultimate, Checkmk Cloud, Checkmk Ultimate MT

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

This allows checking the certificate of IMAP servers that require a STARTTLS procedure to use TLS (SSL), for example on port 143.

This change has already been released with Checkmk 2.5.0b1.

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