I can’t send emails. I am receiving but unable to send. Keep getting an error message saying the connection to the outgoing server failed.

Good afternoon, Craig.

Welcome to Microsoft Community!

I understand you're having trouble sending emails using your email account added to the Outlook for Windows app. Receiving emails on the other hand is not an issue.

This issue may be caused by e-mail account settings that need to be changed. Or it may also be a problem with the application or computer you are using to send and receive emails. So, let's work together as a team to get to the bottom of this. But to better assist you I need to ask:

1. What version of Office are you using? Microsoft 365 Personal? Microsoft 365 Family? Microsoft 365 Business Standard? Microsoft 365 Apps for Enterprise? Office 2016? Office 2019? Office 2021? I specifically need the Product name and Version number as highlighted in the guide and photo below.

https://support.microsoft.com/en-us/office/about-office-what-version-of-office-am-i-using-932788b8-a3ce-44bf-bb09-e334518b8b19

..

2. What email address added to Outlook are you experiencing this sending issue with? No need for the actual address. I just need to know if it's @Outlook.com or @Gmail.com or @Yahoo.com or something else.
3. When did you start experiencing this issue? An exact date of when this issue occurred could prove helpful. If not possible an estimate in days, weeks or months will be fine too.
4. If you send an email, do you receive a bounce message afterwards? A bounce message is a notification that is automatically sent to the sender if an email is not delivered to the recipient for various reasons.
5. If you logged-in to your email account using a web browser instead of the Outlook app does the same sending issue occur?

Hope to hear from you soon.

Respectfully,

Glenn Rue

Forum Moderator

Microsoft Community

i am using Office 2019

Outlook.com

August 2023 was the last email i could send

it tells me ' Unable to send message 0x8004210B No response from sending SMTP server

it works if i use a web browser instead of outlook

1. I am using microsoft office 2010.

******@gmail.com

3.January 10, 2024

4. Yes.
5. Yes

Hello!

We haven't heard from you, so we assume that your issue has already been addressed. We will not be monitoring this thread moving forward so, if you need further assistance, please create a new thread to discuss these concerns by clicking this link: Create a new question or start a discussion (microsoft.com)

Thank you for understanding.

Respectfully,

Glenn