In a few days the basic authentication mode (which could be forced through the portal) will be unavailable. To allow e.g. mail sending from pop3,imap powershell. The advanced authentication mode OAuth2 must be used. Quick setup of modern authentication Step 1, create app Azure Create an application in Microsoft Azure https://portal.azure.com/#view/Microsoft_AAD_RegisteredApps/CreateApplicationBlade/quickStartType~/null/isMSAApp~/false Create a name forSigue leyendo «End to Basic Authentication MS365»