Microsoft Office 2021 LTSC Professional Plus (Version 16) is the definitive choice for enterprises and regulated environments that require the reliability of a perpetual, one-time purchase without the frequent feature updates of a subscription model. Unlike consumer versions, this Long-Term Servicing Channel (LTSC) edition provides five years of Mainstream Support and remains locked in its feature set once installed. Key Features of Professional Plus 2021
A: No. Office 2016, 2019, and 2021 all share version number 16.0 internally. The branding (2021) indicates the feature set. microsoft office 2021 ltsc professional plus 16 link
A: No. You must uninstall the old version and install the new one using a new license key. Microsoft Office 2021 LTSC Professional Plus (Version 16)
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