Chances are that if you use a laptop outside of your office, you’ve been able to retrieve your email using your favourite email client, but then find yourself unable to reply or send new messages.  Lets examine the reasons for this so we can then implement the best solution for your situation.


A number of years ago some of the large email service providers started looking for ways to reduce the volume of email that they have to process, in particular due to the effect of some types of viruses that would automatically send out copies of themselves to all addresses in the user’s contact list without the user’s knowledge.  As often is the case, the legitimate users are the ones that end up paying the price by finding that they are at a hotel or other internet connection through a provider other than their office service provider, and they cannot send email.

Email is sent out using the SMTP protocol (see this article for more info on email protocols).  To send an email item, the computer must open a communication port and send out all communication using this port.  The default designated port for SMTP communication is port 25.  What many internet service providers do is that they intercept all communications on this port and check to see where the client computer is trying to communicate to.  If the destination server is outside of their data network, they block the communication.  Fortunately there are several solutions available.

The simplest and least expensive is to use a different port.  Go to the SMTP server or Outgoing server address setting in your email client software, and change the default port from 25.  Your email will still be sent to your service provider’s email server, but over a different port.  The most common alternate ports are 587 and 1025, 2525, and 8025.  These alternate port settings are dependent on your service provider.  Try these first.  If none of them work, you may need to contact your service provider’s technical support department or their support site to see what alternate SMTP ports they have available.  If they don’t have one, you may have to go to the second solution below.

The alternate solution is to use a third party provider that will accept the email (using an alternate port as mentioned above).  One such service is SMTP2GO.COM.  Their service is very reliable and effective and costs as little as $1.99 per month, with a 7 day free trial.



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