How to check before upgrade forest function and domain function level

[Tien Ngo Thanh]

We have windows 2012 r2 and forest function is 2008 R2 , domain function is 2008 R2.should check what's conditional to can upgrade to 2012 r2 for both forest and domain.our environment has sharepoint 2019 , dynamic crm 2015, exchange 2013 , adfs 2012 r2

[#2]

I'd check domain health is 100% as first step. (dcdiag / repadmin) As to other product I'd try asking in dedicated forums here.

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