Why doesn't Outlook mark a task/reminder complete???

Question

I got into Outlook, and immediately it starts popping up a reminder of a task I had marked complete in the past. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again. I mark it complete again, and it pops up the reminder again.

What in heck is wrong with Outlook??? The looked for the reminder in TODO in Outlook, but it is not there, because as I said, it has been completed.

Answer 1

This behavior matches a known Outlook issue where reminders or tasks appear again after being dismissed or marked complete.

For appointments synced to certain devices (for example, Windows Phone 8), Outlook reminders can reappear even after being dismissed. Microsoft has confirmed this as a product problem and is still investigating, with no user-side permanent fix documented yet.

If the reminder is not visible in To-Do or Tasks but still pops up, it is likely due to this underlying reminder issue rather than anything misconfigured in the current profile.

If reminders in general are not behaving correctly (for example, some do not appear, or Outlook reports problems reading reminders), this can also be part of a broader reminder corruption issue. In such cases, Microsoft guidance focuses on ensuring reminder display is enabled and controlled correctly (including via Group Policy or registry), but the context provided does not include a specific step-by-step repair for a single “ghost” task reminder.

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References:

• Outlook appointment reminder reappears after you dismiss it if it is synced to Windows Phone 8
• Outlook issues, including reminders that fail to appear, messages stuck in the Outbox, and Desktop Search indexing problems
• Reminders in Outlook do not appear