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Autoroute SMTP (ARS) is designed for automatic switching between SMTP servers depending on what network you are currently working in. E.g. you have two Internet service providers - FIRST and SECOND. Normally, IP address authorisation is used for SMTP servers, therefore when you are connected to the FIRST ISP you can send mail to any e-mail address from any e-mail address through his mail server (e.g., SMTP.FIRST.COM). In the same way, having established connection with the SECOND ISP you can freely use its server SMTP.SECOND.COM. But not vice versa. Normally, in that situation user has to get a e-mail address from a free mail server and use its SMTP server to deliver mail, though server of ones ISP ensures much faster and more convenient delivery. The problem is that one has two ISP's. Autoroute SMTP offers solution for that problem. The only thing you have to do is to enter one mail server with address localhost (or 127.0.0.1) in your mail client settings. Then, the mail client will establish connection with Autoroute SMTP, and Autoroute SMTP will automatically switch it to the right server. To choose the right server, Autoroute SMTP compares your IP address to IP addresses of SMTP servers you have entered and chooses one that is located in your sub-net. If no server was found, Autoroute SMTP can use server your specified in the settings. You can also disable automatic server detection, or even choose a mail server in automatic mode yourself from the list you have created by clicking the "Next > > " button. With Autoroute SMTP you always can easily show the way to your letters.