======The ISP needs SMTP Authentication======
If your ISP needs you to use SMTP authentication when sending mail to them, then you just need to tell VPOP3 to use authentication when sending.

Click the **Mail Connectors** button at the top of the page, then click on the relevant **Mail Sender** on the left of the screen.

In the **Settings** tab, check the box called ''This server requires SMTP authentication'' and enter the appropriate username & password in the ''SMTP Username'' and ''SMTP Password'' boxes (these values are given to you by your ISP)

The ''Authentication Method'' can usually be left at ''Automatic'' for VPOP3 to choose the most secure authentication method supported by both the ISP and VPOP3.

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