“An attempt was made to access a socket in a way forbidden by its access permissions” while using SMTP

Question

I am trying to send an SMTP email when certain values in database crosses its threshold value.

I have already allowed ports 25,587 and 465 in the Windows firewall an

Answer 1

If the other answers don't work you can check if something else is using the port with netstat:

netstat -ano | findstr

If nothing is already using it, the port might be excluded, try this command to see if the range is blocked by something else:

netsh interface ipv4 show excludedportrange protocol=tcp