Fix Microsoft Sign-In Window Keeps Spinning on Mac
Question details
The user is unable to log into Microsoft Office on a Mac because the sign-in pop-up window gets stuck in an endless spinning or loading state after entering a valid email address.
- Product
- Microsoft Office for Mac
- Device & OS
- macOS
- Scenario
- Attempting to sign in to activate Microsoft Office applications on a Mac running an older operating system.
- Observed behavior
- After submitting a valid email address, the Microsoft sign-in pop-up window continuously spins without progressing to the password prompt or completing the login.
Verify your current macOS version by clicking the Apple menu and selecting 'About This Mac', and ensure you are connected to a stable internet network without an active VPN.
Update Microsoft Office via AutoUpdate
Installing the latest version of Office supported by your macOS can resolve sign-in loops caused by deprecated authentication protocols.
Older versions of Microsoft Office (such as 16.21) may fail to connect to Microsoft's modern sign-in servers, resulting in a continuous spinning window. Using the Microsoft AutoUpdate tool ensures your software is patched to the latest supported release for your operating system.
Open any Office application like Word, click on the 'Help' menu at the top of the screen, and select 'Check for Updates'.
If the AutoUpdate utility finds a newer version (e.g., version 16.43 for macOS High Sierra), click 'Update' to download and install the software.
Once the update is complete, restart your Mac, open Microsoft Word, and try signing in again.
Uninstall and Reinstall a Compatible Office Release
If AutoUpdate fails to locate updates or your Office installation is corrupted, manually installing the appropriate Office version for your macOS is necessary.
Switch to WPS Office for a Hassle-Free Mac Experience
Tired of frustrating sign-in loops and activation errors on your Mac? WPS Office offers a lightweight, high-performance alternative that doesn't require complex authentication just to open a document.
- 1. Download the Mac Installer: Visit the official WPS Office website and download the free installation package tailored for macOS.
- 2. Install WPS Office: Open the downloaded file and drag the WPS Office icon into your Applications folder.
- 3. Open Your Documents: Launch WPS Office and instantly open, edit, or save your existing Microsoft Office files without any compatibility issues.
Frequently Asked Questions
Why does the Microsoft sign-in window keep spinning on my Mac?
This typically occurs when using an outdated version of Microsoft Office on an older macOS (like High Sierra). The outdated software struggles to communicate with Microsoft's modern authentication servers, causing an infinite loading loop.
What is the last supported version of Office for macOS High Sierra?
The final supported release of Microsoft Office for macOS High Sierra 10.13.6 is version 16.43. Newer updates are not compatible and will not be offered through Microsoft AutoUpdate.
Will upgrading my macOS fix the Microsoft sign-in loop?
Yes. Upgrading your Mac to a newer macOS version (if your hardware allows it) enables you to install the latest and fully supported Microsoft 365 apps, which permanently resolves most sign-in and server connection bugs.
