Google to restricts access to IMAP, SMTP, POP to OAuth this year

As part of our commitment to user safety, Google Workspace will no longer support the sign-in method for third-party apps or devices that require users to share their Google username and password. This antiquated sign-in method, known as Less Secure Apps (LSAs), puts users at an additional risk since it requires sharing Google Account credentials with third-party apps and devices that can make it easier for bad actors to gain unauthorized access to your account.

Instead, you'll need to use the option to Sign-In with Google, which is a safer and more secure way to sync your email to other apps. Sign-in with Google leverages industry standard and more secure OAuth method of authentication already used by the vast majority of third-party apps and devices.

Google Workspace Updates

What this means is that all third-party apps that require password-only access to Gmail, Google Calendar, Contacts via protocols such as CalDAV, CardDAV, IMAP, SMTP, and POP" will no longer work. Crucial to note, however, is that App Passwords will continue to work, which is good news, because without App Passwords, older IMAP email clients without OAuth support, such as the ones often used on legacy or minor operating systems, would cease to work with Gmail.