Using classic Outlook for Windows in business environments
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According to this issue, there was a service incident happening in Outlook between July 9-10, but it has been restored.
You could double-check by visiting this page: https://status.cloud.microsoft/m365/referrer=serviceStatusRedirect > Expand Microsoft's Consumer Products > Outlook.com.
Please try to access your email again and let me know if you could access it again.
My apology for any inconveniences caused by this issue!
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