Fixing thunderbird configuration could not be verified gmail

For past couple of days I have been trying to configure Thunderbird to access my mails from new gmail account  in office and it was reporting me "configuration could not be verified gmail" I was troubled because I was using Thunderbird for quite a long time without any problem.

After googling around I doubted, it may be due to antivirus/firewall I am using AVG Internet Security, to test I disabled Firewall and check, but this did not help. Also nothing succeed even after disabling antivirus..

To test the problem I used my old gmail ID and, Wow! it configured, but the new email id still reporting the same problem. Now it was clear that the problem is with new email id and not with thunderbird. This hinted me to check the configuration on gmail server. Now I was sure that after bit of searching and experimenting this problem can be fixed.

I visited the settings of my mail account and saw a link that says 'Forwarding and POP/IMAP' I was under impression that this link is just to manage email forwarding. still I clicked and found that IMAP was disabled. Unfortunately still thunderbird was not working and reporting similar error..

Finally I visited https://www.google.com/settings/u/2/security/lesssecureapps   after reading following page

and enabled the access for less secure apps. I did checked this setting for my old email id before applying this setting to my new official account. 

Thank God, the Thunderbird is configured to access my emails now.

useful link: 

https://support.google.com/mail/troubleshooter/1668960?authuser=1&rd=1#ts=1665018,1665141,2769074

I hope this article will be helpful to all those who want to use thunderbird or other similar email client to access their emails

Regards

IT Pundit