Error Code: -17884 An unknown error has occurred in Outlook?

Question

Error Code: -17884 An unknown error has occurred in Outlook?

Answer 1

Hello Nathan Brown6, Good morning!Thank you for publishing in Microsoft Community. We are happy to help you.Based on the description you have shared; we understand that  you are getting Error Code: -17884 An unknown error has occurred in Outlookwe need to double check if the issue is related to the account or outlook for Mac.  Outlook for Mac Error 17884However, to better understand the problem , we need more details from you, please provide us with the following information. Thank you.1- Please may i know if you are facing the issue as well in outlook on the web? if yes let me know2-Please if you not facing the issue on the web version kindly try the below steps: . Open Outlook and make Outlook 'Work Offline' ( by navigating to Outlook menu bar> Outlook> Work Offline)
. Quit and restart Outlook.
. Send a test email to yourself (This email will get stuck in Outbox as Outlook is Offline)
. Go to the Outbox folder and delete all the emails in it.
. Now switch to 'Work Online' and try sending an email. 
. Also empty your Deleted Item/Trash folder

The issue can be related also to too many simultaneous connections to your exchange so you need to close all application on Mac and only open your outlook for Mac and check the issue.

3-check if you got Throttling policy for EWS to unlimited for the affected users. 

Meantime, we have limited knowledge for outlook for Mac If the issue still persist , to further help you, you are recommended to contact our related team (outlook for Mac) to seek further assistance via Outlook->Help->Contact Support, as it is a dedicated channel handling Outlook for Mac issue. You can provide the version number and full screenshot of error messages to them for analyzing. Thanks for your time and understanding. Contact support within Outlook for Mac - Microsoft Support

For other concerns, please do not hesitate to add you post in the Microsoft Community Team. 

Thank you for choosing Microsoft as your partner in business.SincerelyEben Ezer Tres | Microsoft Community Moderator

Answer 2

Dear Nathan Brown6,

Good day! Thank for posting in the community.

We've received your query, and you can expect to receive response from one of our community moderators accordingly.

At this point, we appreciate your patience and cooperation. Thank you.

Sincerely,

Community moderator