First, make sure you have checked in the account properties of the Outlook Express / MS Outlook the option “My server requires authentication”. Please note that if you are using a different email client the settings might be different.

If not, proceed to the following test. Open Command Prompt (Windows -> Start menu -> Run -> type “cmd”) and type:

For clients with premium hosting accounts:
telnet 25

For free hosting clients:
telnet 25
Press “Enter”

If you do not get a response 220 mail server or 220 mail server this means your PC (Firewall or Antivirus Program) blocks port 25 and thus filters your outgoing emails.

Solution: Disable the option of your/your network firewall to block port 25, contact system administrator, ISP, or Antivirus Program producer for help on how to disable port 25 filterings. Alternatively, you may use port 587.

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