Late last night we became aware of an issue with MS13-061 security update for Exchange Server 2013. Specifically, after the installation of the security update, the Content Index for mailbox databa...
Updated Jul 01, 2019
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@So now I'm confused, that falls in line exactly with the process I mention above. We may not issue security updates for more than N-1 back (which is RTM in this case), but the code is still _very_ much supported. If you were to call support for RTM they would certainly work with you and not force you to upgrade to CU1 to troubleshoot an issue. They may however suggest you upgrade if the issue you called in about is a known-fix in an already released CU. If however you felt a certain security update released for N or N-1 was something you need, then at that point you would need to upgrade to at least N-1. Being under 'supported' does not mean the same thing as a guarantee for patches to be released. We still support Exchange Server 2003 SP2, but there have been no new updates for it in a long time.