I started seeing a lot of Gmail users asking for help because Outlook stopped syncing. It was perplexing until one client wanted me to fix it for him. While I was looking at his computer, he told me Google sent him an email because someone tried to connect to his account and the email included a list of steps to take to insure the account was secure. He went through the steps and made the changes they suggested. One of the steps was to turn off the allow less secure apps options, which he did. (The "someone" turned out to be himself while using a hotspot.)
Other people said Google sent them an email recommending a security checkup or saying they were using less secure apps or and they took Google's advice to disable less secure apps.
Unfortunately, when less secure apps are not allowed, Outlook can't connect to Gmail servers, unless you also enable two-factor authorization then use an app password in Outlook. (The app password is a one-time use password that can be voided if you suspect it is compromised, without affecting your “real” password.)
My recommendation is to turn off less secure apps and enable two-factor auth. In Gmail's implementation, you'll receive a code by text message to enter when the second authorization screen comes up. If you use an application, such as Outlook, that does not yet support the second authorization, you'll need to use an app password.
To check or change your settings, sign in to Gmail then open your Google account settings. If two-factor authentication is not enabled, the option to allow less secure apps is at the end of the page.
If you enable two-factor authentication, you'll create new app passwords at App passwords. Gmail allows you to revoke individual app passwords, which you can do by clicking the trash can icon to the right of the device name.
In my experience with Gmail, their implememation of two-factor authorization is not annoying at all and retains the authorization. It doesn't request re-authorization often, which makes using an app password fairly painless. If you use public hotspots, you should enable two-factor.
If you choose to allow less secure apps, is it really insecure? No, it's just not as secure as using the newer OAuth protocol to login. Less secure apps use plain username/password authentication to access an account instead of OAuth 2.0. The username password should be transferred in a secure channel but there may be points where a sniffer could pick it up.
More Information
Gmail in Outlook: unable to connect to email
"Less Secure Login Warnings"
My issue is a little different...I can see my father-in-laws google calendar in outlook. He does have a bunch of baseball schedules that I do not need to see. He has them marked private, and I still see them. How can to stop that?
One of the best and straight forward write-up on this topic. The App Password link is most helpful and I have not found any other blogs writers mention it. Most helpful for working with 2-factor authentication on Gmail and Outlook or other mail app. Thanks a ton
Kindly reply point wise
1) Can you explain in simple steps considering less secure apps is closed by google now then what to do to ensure outlook still works.
2) If 2 step authentication is enabled in admin i guess even if less secure apps is closed by google still outlook works fine. As per above article only one time app password to enter in outlook and thats it continue to use.
In this case how to generate one time app password. Please give simple steps.
3) Also finally OAuth 2.0 is all difficult and cant really understand steps. Can u tell me in simple step by step how to authenticate users using OAuth 2.0 once less secure apps is disabled by google.
4) Once less secure apps is disabled by google can 2 factor authentication enable be done to ensure if any user is still not able to use outlook he can use it.
5) I believe that once google discontinue less secure apps if 2 step authentication is enabled and forced and users have done steps then it wont affect their outlook please confirm this or clarify if i am wrong
thank you very much after 2 hours of figuring what i did wrong this worked first time.
It is irritating that Google think Outlook is insecure and something they do on purpose to annoy everybody not thinking that Google should be allowed to have all info from everybody in order to fill their own pockets.
I am not a technical person and all of this is confusing to me. Is there a simpler "Dummies" version to do this? Thank you
Probably not... Start with logging into your google profile at https://myaccount.google.com/security#signin. You can either allow less secure apps or enable 2 factor auth and create an app password to use in outlook.
Thanks a million for posting this assistance. You are a lifesaver.
Thanks, this article helped a lot. You may want to mention that if you enable two factor authentication in Google, Google automatically removes the option to turn on "Less Secure App Access."