CAS Duo 2-factor authentication not working

I am authenticating into a google for work gmail address. That authentication is through CAS / Duo (two factor authentication).

It appears that the two factor authentication is failing because Duo requires JavaScript and the em client does not have JavaScript enabled.

Does anyone have a work around or solution for this issue. I am unable to turn off 2-factor authentication since is set at the Domain level


Scott B

Hi Scott,
can you check which version of eM Client you’re running in Help>About? This issue should have been fixed in the latest update.
Alternatively, make sure you have javascript enabled in Internet Explorer.


Thank you for the quick reply. I am using em 6.0.24144.0
Windows 10
IE 11.20

Javascript is enabled in Internet Explorer.

Hi Scott,
I have not noticed that your google account doesn’t use the google’s native 2-step verification through oAuth but some different service.
The problem might be the same we encountered (and fixed for oAuth) that your verification provider does not support Internet Explorer.
Seeing as current version of eM Client uses IE core for some of it’s features, it won’t let our app verify it.
This issue should be gone in version 7, because we are getting rid of the IE core, but that one is still in Alpha testing.
I am sorry for the inconvenience.