Microsoft Outlook Bug Affects Excel Attachments with Non-ASCII Characters

Microsoft Outlook Bug Affects Excel Attachments with Non-ASCII Characters

First seen 2 Dec 2025, 16:44 UTC •BleepingcomputerFeeds.4Sysops •24.3

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Microsoft is addressing an issue in the new Outlook client that prevents Exchange Online customers from opening Excel attachments with non-ASCII characters in their filenames. The problem has been present since at least November 23, 2025, and displays an error message stating, 'Try opening the file again later.' A fix has been deployed to resolve the encoding error causing this issue.

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