When configuring your Gmail account in Outlook (or other mail clients such as Thunderbird and Mail apps on (older) smartphones), you may run into continuous password prompts or sync errors.
This is because Google has turned off Basic Authentication (which they refer to as Less Secure App Access) for all accounts since May 30, 2022. It now only lets you authenticate via the OAuth 2.0 standard.
As a result, you’ll get Send/Receive errors (0x800CCC0E) and could get prompted for your Gmail password again in Outlook and the login could fail even when you supply the correct password.
Continue reading: Outlook can’t connect to Gmail: Password incorrect