Change stream · Classic Outlook known issues
[FIXED] Error opening classic Outlook: "Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot be opened. The attempt to log on to Microsoft Exchange has failed."
1 Oct 2025 · Outlook
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Error opening classic Outlook: "Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot be opened. The attempt to log on…
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