Login to https site from Windows without specifying domain

I have added a network calendar (served by radicale) to Outlook: screenshot of step one

Now a Windows security message is raised asking for login credentials. Windows screen asking for credentials

However, the domain of the computer is automatically added computername\user, while the server expect to recieve user only.

How can I login without prepending a domain name to the username?


Solution 1:

In username field just write a backslash before your username:

\username

You'll see that the domain will remain empty.

Solution 2:

Click on more choices. Enter the desired username and password.