Unable to Set or Send Emails

Hello All:
I am a newbie and would like some assistance. I installed owncloud 13.0.0 and am unable to set personal email for profile to reset password. also I cant upload or sync the calendar to send schedules - email just don't work. we use php or send mail and choose not to use stmp or imap. this is the error we get:

idn_to_ascii() expects parameter 3 to be long, string given at /home/mywebsiteurl/public_html/portal/lib/private/Mail/Mailer.php#212

we don't know how to fix..we found the idn_to_ascii...

EVEN if we go into files and mannual enter the data, it will not work. we cant send data reports to owncloud server for this reason either the error says: no app in context

Hi again,

this is a nextCloud version, and nextCloud has his own forum where you can get help.