Bugs and issues found on or specific to unsupported operating systems will no longer be investigated or fixed.New installations on unsupported operating systems will be blocked.It is not advised to continue to run on these unsupported operating systems. These clients will continue to run, but their functionality will no longer be tested. Existing OneDrive sync app installations on unsupported operating systems will stop updating.How users will be impacted on September 10 th, 2021:

Note: Both macOS Sierra 10.12 and macOS High Sierra 10.13 have been out of Apple’s mainline support since September 2019 and November 2020, respectively. This update will impact both OneDrive business and personal users. Starting September 10, 2021, we are ending support for the OneDrive sync app on macOS Sierra 10.12 and macOS High Sierra 10.13 and focusing our resources on new technologies and supported operating systems. The OneDrive team is committed to bringing you the best, most secure experience possible across your devices.

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