unable to send emails via webmail

[nitamc]

Hi,
When sending messages via webmail on Horde, Squirrelmail or Roundcube I am getting the following message:

Unknown response 435 Unable to authenticate at present

I am receiving emails ok
Can someone please help

Thanks

[thewebhosting]

Kindly check the email error logs for the exact error message. You can get the error logs from the below mentioned location:

/var/logs/exim_mainlog.