I had this error and it was caused by an incorrect password for the email account.
Hello,
I have a simillar problem. No matter how I set dns,different smtp servers (with and without ssl/tsl), error 016-781 still persist :(
There is no problem with remote printing.
You will likely need to do a Wireshark trace if it is still giving the same fault. As I stated, it means no connection, if Gateway,DNS,Proxy(If in use) and time are correct it should not happen unless the domain in question is down. It can't be firmware related because it doesn't get to the point of not being compatible
The problem is not solved.
Are there any other options?
Thank you
016-781 means there is no communication to mail.smtp2go.com, which implies a trouble in the DNS.
I see your gateway is just 192.168.1.1, but your DNS is 192.168.1.10, odd , but not impossible.
I would suggest though,disabling Obtain DNS Server address Automatically and then setting the secondary DNS to 8.8.8.8
Hello
On the machine when scanning an error
The credentials are current, other functions work.