Maintenance work: Groupware service – certificate renewal
On 07.10.2025 between 09.00 a.m. and 11.00 a.m.
2025/09/29
+++ 07.10.2025 10:35 a.m.: The maintenance work has been successfully completed. On all Exchange servers of the groupware service, the certificates were replaced with new certificates signed by HARICA. In addition, a cross-certificate is provided so that the new certificates can be validated with both the HARICA root certificate from 2015 and the one from 2021. +++ During the specified period, the TLS certificates for the groupware service's Exchange servers will be renewed. This is the first certificate for the groupware service that has been signed by DFN's new contractual partner (HARICA).
Please note: Some systems do not yet contain the current HARICA root certificate. In these cases, the HARICA root certificate from 2021 (valid until 2045, RSA) must be installed manually.
Further information and instructions can be found here:
server certificates (opens in new tab)
https://doku.tid.dfn.de/de:dfnpki:tcs:2025:cacerts (opens in new tab) (in German)
