Hi @Petzinger, Sean
Welcome to our forum!
To better assist you to solve the problem, could you please describe more about the issue?
- Does the issue occur recently on Outlook Desktop Client? Do you have any specific operation before the issue occurred?
- What is the version of your Outlook? It is recommended that you please check the Outlook client version (File>Office Account>Product Information) and try to upgrade to the latest version to see if the problem is resolved.
- Would you please provide a screenshot of the issue? (In order to avoid privacy leakage, please remember to hide your personal information.)
In addition, please go to File>Options>Trust Center>Trust Center Settings>Email Security to check if you untick "Read all standard messages in plain text". More information: Read email messages in plain text - Microsoft Support
Hope it helps!
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