Hi @Morten Fly
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Based on my research, Microsoft has acknowledged this issue and is currently investigating it in Outlook Classic for Windows. The behavior you’re experiencing, where Danish characters such as æ, Æ, ø, Ø, å, Å are replaced with “?”, matches the issue Microsoft has listed as affecting recent Classic Outlook builds.
As a workaround, you could consider the following options:
Use Outlook Web Access (OWA) or the New Outlook.
This can temporarily help you avoid the issue in Classic Outlook. You’ve already noticed that New Outlook works correctly, which confirms you’re affected by the same known issue.
Revert Classic Outlook to the previous version (Version 2512, Build 19530.20184).
You could consider rolling back to the previous working build and temporarily disable updates. After Microsoft releases a newer update, you can enable updates again and re‑test to confirm whether the issue is still present.
Disable Outlook automatically selecting the encoding for outgoing messages
Go to File > Options > Advanced.
Under International Options, uncheck Automatically select encoding for outgoing messages.
Remember to set a reminder for March 10th to re‑enable this option, or check back on the Known Issue page to see if Microsoft has released a fix earlier.
You can refer more via: Classic Outlook replaces accented and extended characters with question marks - Microsoft Support
If you have any additional concerns, feel free to comment below. I would be more than happy to assist.
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