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While uninstalling old versions of office is technically not required per communication from Microsoft or even recommended by them, you may want to do so anyway and then reboot before installing new versions to avoid files being carried forward from older versions of Office that may or may not be fully compatible. ECI is not responsible for lost files, contacts, etc.. so please back up all work and configurations you wish to save before doing any install.
For Mac: Office 365, 2016, 2019, 2021, etc.. all use the same combined installer that can be downloaded directly from Microsoft, but different Serializers and different Config files. Config files are OS dependent and config files from multiple versions may conflict.
Microsoft does not recommend using time machine backup to transfer Microsoft Office from an older Mac to a newer Mac and instead recommends doing a fresh install.
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For Macs: Once you login to the above portal and download the Office 2021 zip file, it will unzip into a folder with two packages, a base installer and serializer, both need to be run for Office 2021 to work. Office is registered with a serial number, when opening office for the first time, DO NOT SIGN IN, if you sign in, it will wipe the serial number and attempt to register the software with a Microsoft account. When launching office for the very fist time, just click the small-font option that says "skip" the login. You can then open a new office document. |
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