Go to Setup, Settings, Email. Use PHPMailer
Outlook/Office accounts are not supported for sending emails via SMTP as Microsoft dropped support for the regular SMTP connection.
Google works well, but you need to setup "Less Secure Apps". (Google Business)
Email Protocol
SMTP, Sendmail, and Mail.
It’s highly recommended to configure the SMTP protocol for sending emails if you don’t want to encounter issues with emails going to spam or encoding, the examples below will be strictly for the SMTP protocol as it’s the recommended one.
Email Encryption
SSL – Select if you are configuring SMTP with port 465
TLS – Select if you are configuring SMTP with port 587
None – Select if you are configuring SMTP with port 25
Summarized, SSL works with port 465, TLS works with port 587 and if you are trying to configure the SMTP config with port 25 (non-secure) there will be no encryption and you should select None.
SMTP Host
Enter your SMTP hostname.
SMTP Port
Enter your SMTP port
Don’t mix up these modes; Email encryption set to SSL on port 587 or TLS on port 465 will not work.
Email
Enter the SMTP email you are trying to configure as a general email for the CRM, in most cases, this will be a mail only used for sending emails from the CRM, e.q. you can create an email account with name no-reply@ or info@, however, this is up to you to determine how best fit for your needs.
SMTP Username
It's usually your email address.
SMTP Password
Fill the password for login, you should already know your password.
Email Charset
The default is UTF-8, you won’t need to change this ever, because in most cases this works fine, however, if you decide to change the encoding it’s highly recommended perform few researches to see what encoding is best fit for you.
BCC All Emails To
You can add email to be added as BCC header if you want to keep track and get copies of all emails sent from the CRM if you need to add multiple BCC emails, separate them by a comma.
Email Signature
Global email signature for all emails sent, can be used as merge field added in email templates in Setup->Email Templates, keep in mind this option can be overridden if e.q. the staff that is sending an invoice to an email have configured custom email signature in his profile.
Predefined Header & Predefined Footer
The CRM installation by default comes with a predefined header and predefined footer for all email templates, the predefined header and footer is pretty clean but if you need something more then this, feel free to adjust the code.
The email message contents are merged in between the predefined header and footer e.q.
[predefined header code]
The email message
[predefined footer code]