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For better research, please provide more details about this case:
Does the problem occur in the Outlook desktop client?
What's the version of your Outlook? (File > Office Account > About Outlook).
Is there a problem with the scroll bar elsewhere in Outlook? For example, mailing lists.
Here are a few steps you can try to resolve it:
- Update Outlook: Ensure your Outlook is updated to the latest version. Sometimes, these issues are fixed in newer updates.
- Check Add-ins: Sometimes, add-ins can cause such issues. Try disabling them to see if it helps. Go to File > Options > Add-ins, then disable them.
- Repair Office: You can try repairing your Office installation. Go to Control Panel > Programs and Features, select Microsoft Office, and choose Change. Then select Quick Repair or Online Repair.
Hope this helps!
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