about 2 day ago i get a message like in photo. i have 2 mail accounts configured on emclient. works fine about 1 year. from 2 days, at second account i receive error mesage. i delete this account and reconfigure but i have same problem. anyone have an idea? thanx a lot. 
solved. hi again. after i post that error a have a new idea. i verify if yahoo make this days some changes at security. i saw that they introduce a new ”Allow apps that use less secure sign in” in account settings. i marked that option and second acount in emclient works fine now. thanks for disturb anyone of u but i hope i help somebody with this problem.
Hello Razvan,
thank yu sharing the solution to your issue on the forum.
Regards,
Olivia