Many ISPs (Internet Service Providers) are blocking what is called "Port 25" which is the port used to send emails. They are doing this to cut down on the amount of spam that is sent from their networks. All email sent via the Internet is routed through the Port 25, the TCP (Transmission Control Protocol) channel used for communication between an email client and an email server.
Port 25 blocking allows ISPs to block spam sent out through their networks, but it tends to punish the innocent that have a need to send through email servers other than those belonging to their ISP. The ISPs that block port 25 require their SMTP server to be used instead of the remote SMTP server or a SMTP server running on your computer/server.
So whether it's your server being blocked from sending emails direct or a end-user client (such as a PC, Mac, Portable device) the simple solution is to send all your outbound emails via a SMTP Relay as known as a Smart Host.
outMail is a secure and authenticated SMTP Mail Relay which supports TCP Port 25 and many other alternative ports. You are no longer restricted by your ISP and can send emails anytime from any location which is great news for your laptop and portable devices.
About Prolateral
Prolateral Consulting is in business to put your organisation back in control of your own Information Technology, specialising in information and messaging security, computer forensic services, and disaster recovery planing.
Contact Info
Prolateral Consulting Ltd
Luton, Bedfordshire, UK
Tel : +44 (0) 8450 763760
Email :
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