GMail IMAP NO [AUTHENTICATIONFAILED] Invalid credentials (Failure)

You passed the correct login/password to login to imap.gmail.com, but you still get an “Invalid credentials” error.  What gives? For example, you called Chilkat’s Imap.Login method, passing the correct login/password, and the imap.LastErrorText contains this: authenticateLogin(110ms): loginImap(110ms): ConnectionType: SSL/TLS ImapCmdSent: aaab LOGIN “you@gmail.com” getCompleteResponse(110ms): ImapCmdResp: aaab NO [AUTHENTICATIONFAILED] Invalid credentials (Failure) –getCompleteResponse –loginImap isOK: serverResponse: aaab NO [AUTHENTICATIONFAILED] Invalid credentials […]

GMail IMAP OAuth2 – A Walkthrough

This blog post covers from start to finish the process for getting a desktop application working with GMail using the IMAP protocol with OAuth2 authentication. Start here:  https://console.developers.google.com/apis/credentials (1) The first step is to create credentials.  Your app is a desktop application.  HOWEVER, you will be creating credentials as if your app is a web app. See this YouTube video […]