No puedo cambiar contraseña ni enviar ni recibir correos

no puedo acceder a mi cuenta me pide la contraseña y no la reconoce, no recibo ni puedo enviar correo

Sometimes the server will not accept passwords if the security policy for the account is incorrectly setup in eM Client. Go to Menu > Tools > Accounts, and check that you have one of the following combinations selected.

Port 587 = Force usage of SSL/TLS
Port 25 = Use SSL/TLS if available
Port 465 = Use SSL/TLS on special port (legacy)

Port 993 = Use SSL/TLS on special port (legacy)
Port 143 = Use SSL/TLS if available

Port 995 = Use SSL/TLS on special port (legacy)
Port 110 = Use SSL/TLS if available

These are the correct combinations of port and security policy. The underlined ones are the best option for security if your server supports them. SMTP port 465 was reassigned and should no longer be used for SMTP, though many mail providers still recommend and use it.