Miscellaneous topics that do not fit into specific categories.
Hello Phoenix Wei,
Thank you for reaching out in Microsoft Q&A forum.
I understand you’re concerned because the Office Online Viewer (view.officeapps.live.com) is showing “Service Unavailable” errors and you want to know the cause and if there’s any ongoing maintenance or outage.
This issue usually occurs when the Office Online service experiences temporary disruptions.
Please go to https://status.cloud.microsoft/ to check Microsoft’s public status or simply wait and retry later.
If the online viewer is down, open the document in the desktop version of Microsoft Word or Excel as suggested in the error message.
Sometimes cached data causes loading issues. Clear your browser cache and restart the browser.
You can also try to test in another browser or device. This helps confirm if the issue is service-wide or browser-specific.
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