failure when connecting to gmail account

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• Operating System (Linux/Mac/Windows/iOS/Android): IOS 14.3
• Delta Chat Version: 1.14.4
• Expected behavior: Success when using gmail account for the initial server connection.
• Actual behavior: I see two behaviors when I try it from scratch - uninstall app and delete all data.

1. When trying with just username and password, the server connection 80% dialog is shown then the process stops and connection screen remains shown.

2. When using advanced setup, I specify SSL for both imap.gmail.com and smtp.gmail.com, I get:
   Setup error Please check email address and password.
   The email in the error message is the one I use.
   no response: code: None, info: Some("[AUTHENTICATIONFAILED] Invalid credentials (Failure)")

I tried more than 10 times after confirming the password in standard gmail UI. I checked again in gmail UI after DeltaChat setup failure to confirm that the password is not blocked.

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If I fiddle with the advanced setup by not specifying all fields, I get both behaviours described above: stopping at 80% without success or authenticationfailed.

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I dug deeper and found the FAQ page about providers.
I had missed the "less secure app" setup.

Nevertheless, after enabling "less secure app", connection still does not work.
See attached screenshot

The URL points to email clients setup for gmail which I followed step by step.

Any pointers ?

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My last attempt succeded. I installed the desktop client then managed to setup connection to my gmail account.

When going back to IOS, connection did work right away.

Any hint about what could have happened ?

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After a while, the IOS app sets a message that it cannot connect to the server anymore.

IOW, no functionality anymore.

Has anyone else experienced the same issues with gmail without 2FA ?

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FTR, setting up 2FA and adding an app password enabled the functionality.

[r10s]

thanks for diving into the issue and to document that here 👍

iirc, we "solved" that on android by making urls in the error messages clickable, that helped a lot. i think, this part is missing on ios. and, of course, oauth2 is still missing for gmail as well #92