Hi, Christian de BERAIL
Since the event times themselves appear correct, the white stripe is likely a calendar-view or rendering problem in Outlook, especially if it appeared suddenly after an update.
Here are some suggestions you can try:
Open the calendar in Outlook on the web. If the stripe is not shown there, your events are fine and the issue is limited to the desktop display.
In classic Outlook, open Calendar, select the View tab, then choose Reset View. This restores the default calendar layout and has resolved similar unexpected calendar appearance changes.
Close Outlook, press Windows key + R, enter outlook.exe /safe, and press Enter. If the stripe disappears, disable recently added COM add-ins under File > Options > Add-ins. Safe mode temporarily disables add-ins and custom display settings.
Finally, install the latest Office updates from File > Office Account > Update Options > Update Now, then restart Windows. Recent calendar display problems have previously been corrected through Outlook build updates.
These steps do not change or delete any calendar events.
Thank you for your patience in reading, I hope this information has been helpful to you.
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