Google added a new feature that allows users to disable access from what they call “less secure apps” – or apps that use username and password login (opposed to Google’s OAuth2), which is the case with most email clients! The list of affected apps includes several third-party mail apps including famous clients like Outlook or Thunderbird.
In your google account under “Security” you must allow less secure apps in order to accept connections from Onpipeline’s Email Client https://myaccount.google.com/lesssecureapps
Even if you allow less secure apps, it may happen to receive an email message with something like “Sign-in attempt was blocked” or “Critical security alert”. It may depend on Onpipeline.
Before you become paranoid click on the “check activity” button in the email you received and check who is connecting to you email. If it was from Onpipeline you will see something like the following:
Should you have any doubts please do not hesitate to contact us.