which In-place Upgrade of Windows Server is possible without upgrading the Archive Server?
An inplace upgrade of Windows Server is possible, when the Version of ArchiveServer supports both windows versions.
Archive Server 10.5 only supports Microsoft Windows Server 2012 R2 64-bit. So there is no upgrade of the operating system possible.
AS 10.5 is out of support, the latest support version is AC 16.2.3 and the newest version is AC 23.3. We suggest to upgrade to a new supported version.