To reactivate your Office applications, simply reconnect to the Internet. If you do not connect to the Internet at least every 31 days, your applications will go into reduced functionality mode, which means that you can view or print your documents, but cannot edit the documents or create new ones. You should also connect to the Internet regularly to keep your version of Office up to date and benefit from automatic upgrades. Internet access is also required to access documents stored on OneDrive, unless you install the OneDrive desktop app. For Microsoft 365 plans, Internet access is also needed to manage your subscription account, for example to install Office on other PCs or to change billing options. Internet access is required to install and activate all the latest releases of Office suites and all Microsoft 365 subscription plans. How do I know my PC or Mac can run Office? How do I know if my computer, mobile device, or browser can run Office? Learn more about the differences between Microsoft 365 and Office 2021 in Office Support, or use the comparison chart to help you pick the right Office version for your needs. One-time purchases don’t have an upgrade option, which means if you plan to upgrade to the next major release, you'll have to buy it at full price.

Office 2021 is a one-time purchase that comes with classic apps like Word, Excel, and PowerPoint for PC or Mac, and does not include any of the services that come with a Microsoft 365 subscription. With a subscription, you get the latest versions of the apps and automatically receive updates when they happen. Microsoft 365 also comes with services like 1 TB of OneDrive storage, 60 Skype minutes per month, and Microsoft chat and phone support. The apps can be installed on multiple devices, including PCs, Macs, iPads, iPhones, Android tablets, and Android phones. Microsoft 365 is a subscription that comes with premium apps like Word, Excel, PowerPoint, OneNote, Outlook, Publisher, and Access (Publisher and Access available on PC only).

Microsoft office 2019 update from 2016