Email not sending

Hi there,
Cant send emails via Manager for some reason. I get this message when I press send

System.Net.Mail.SmtpException: System.Net.Mail.SmtpException: 535 5.7.0 Mailgun is not loving your login or password
at System.Net.Mail.SmtpClient.CheckStatus (System.Net.Mail.SmtpClient+SmtpResponse status, System.Int32 i) [0x00020] in :0
at System.Net.Mail.SmtpClient.Authenticate (System.String user, System.String password) [0x0006b] in :0
at System.Net.Mail.SmtpClient.Authenticate () [0x000bd] in :0
at System.Net.Mail.SmtpClient.SendCore (System.Net.Mail.MailMessage message) [0x0015c] in :0
at System.Net.Mail.SmtpClient.SendInternal (System.Net.Mail.MailMessage message) [0x00050] in :0
at System.Net.Mail.SmtpClient.Send (System.Net.Mail.MailMessage message) [0x0009c] in :0

Anyone any idea if this is Manager related as I dont have any issues with sending or receiving emails,
I use Linux but have had no issues up until recently

Maybe see topics under

Read the Guide first: Things have changed.

Hi Tut,
Thanks for that. I got it working now.
Kind regards,

Hi novica,
Appreciate your help. Thanks. It now sends the emails from my own service providers
Kind regards

This was really helpful as I’ve not invoiced for a bit and had the same problem.

Thank you.