Dear all,

we just migrated from google workspace to Microsoft 365. Email sending worked flawlessly with google, but now I can not make it work with Microsoft.

Emission email address matches SMTP username

server = smtp.office365.com

port = 587

smtp helo = companyname.com

authentication = tried all, none of them worked

username= user@companyname.com 

password = generated App-password

STARTTLS = on

Whenever try to send a test email I get:

An error occurred while sending mail (Net::ReadTimeout with OP-11915 

In the MS-tenant admin interface SMPT is enabled.

Hi, I had the same problem in send mail after migrating from Gmail to Microsoft365. 

In my case , I'm getting error message as "An error occurred while sending mail (getaddrinfo: Name or service not known)".

If I try the same credentials and all other settings in windows forms application(using c#), I was able to send mails using MailMessage concept.     

Only additional line that i had added in windows forms application is "System.Net.ServicePointManager.SecurityProtocol = System.Net.SecurityProtocolType.Tls12", In OpenProject is there a way that i can add this line in configuration file manually.

Hi Peter - Did you manage to resolve this as I have the same problem. Thanks

Unfortunately, I'm having the same problem on a Linux system. Has anyone found a solution yet.

Update:

The solution from the following link works for me:

https://community.openproject.org/topics/18896?forum_id=6&r=18897#message-18897

I had te resort to using Mailtrap, so OP sends its messages to mailtrap but mailtrap forwards them transparently as they were sent from our own domain. 

For this, you have to fill in some data at mailtrap so they allow you to send emails using the address/domain. Works tike a charms ever since!

In this case in OP you have to set up SMTP as follows: