I have upgraded my Office suite to 2016 version in Windows 10 computer. When I start using the Outlook 2016, I notice that the calendar reminders don’t pop up and other function are fine. The same problem also happens with Office 365 ProPlus on my Surface Pro 4 tablet. I have created Calendar and Task reminders in my primary folder and it just stop working. How can I resolve it?
Outlook reminders do not clear after pressing dismiss. After pressing 'Dismiss' in the Reminders window, the calendar item clears. When the next reminder comes up. All the previous dismissed reminders fill the Reminder window. After I ran outlook /cleanreminders, Outlook was re-launched and the reminder I had open prior to running outlook /cleanreminders displayed and is now dinging every few seconds, as though there are new reminders. However, there are no new reminders, only the one that was open prior to closing Outlook and running outlook /cleanreminders.



- For example, her outlook 2003 said she had 25 reminders, but when she went in via OWA, it said there were 85. I created a clean profile (non-cached) and it just said she had 90, and now the OWA says 45. I created a profile on an outlook 2007 pc and it said 90 reminders. Will outlook /cleanreminders trash all the dates for follow-up reminders?
- When reminders just won't dismiss, there are several things you can try to get rid of it: 1. USE CLEANREMINDERS SWITCH The easiest way to try to get rid of corrupt reminders is by closing Outlook and reopening. DELETE THE APPOINTMENT Sometimes the cleanreminders switch doesn't help.
In some conditions, you could disable suspicious add-ons or run the software with Safe mode to troubleshoot that. Then you can try any of the tips to fix the issue with Office Outlook in Windows 10 or 8.
The upgraded process may make the Reminders folder to be corrupted or damaged, you could try the method to clear them and regenerated at once.
* First you must close the Microsoft Outlook software.
* Press Win + R from your keyboard to open the Run dialog box.
* Type the command:
outlook.exe /cleanreminders
and click OK button. Running the command will open the Outlook to delete all reminders for email messages, specified appointments and task, and then repair them.
If your mail is configured with Exchange, delete the Corrupted cache. Open the Outlook, go to Options > Calendar options, and then delete offline items.
If it is still not working, go to make changes with registry editor.
* Press Win + R together, type regedit.exe, and click OK button to open the registry editor:
* Locate the tree:

HKEY_CURRENT_USERSoftwareMicrosoftOffice
There should be a 16.0 key if you are using Outlook 2016, or be 15.0 for the 2013 version, and just select this key named 16.0 or 15.0, and continue go to the sub-key:
OutlookOptionsReminders
* Go to its right side pane, hold-and-press or right click on the WindowsPos name to delete the string.
* Finally restart the Outlook to check if it takes effects.

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