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SMTP at charter.net now rejects e-mail messages from addresses that do not match the STMP login which is a problem for TB with where SMTP logins are shared.

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  • Last reply by sfhowes

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My Thunderbird settings are unchanged after many YEARS of successful use and MULTIPLE charter.net e-mail accounts.

Outbound messages now fail with: "An error occurred while sending mail. The mail server responded 5.1.0 <wycoff_it@charter.net> sender rejected. AUP#O-1580. Please verify that your e-mail address is correct in your account settings."

Since multiple Thunderbird e-mail accounts share a "pool" of possible SMTP servers and logins, TB will remain unusable on providers which require the sender e-mail address to match the SMTP login (unless the sending e-mail account randomly matches the corresponding SMTP server login). This appears to be a new "security measure" added by charter.net. It does not affect e-mail applications which associate a specific SMTP server and login with each e-mail account (UNLIKE Thunderbird). Is there any potential fix for this?

My Thunderbird settings are unchanged after many YEARS of successful use and MULTIPLE charter.net e-mail accounts. Outbound messages now fail with: "An error occurred while sending mail. The mail server responded 5.1.0 <wycoff_it@charter.net> sender rejected. AUP#O-1580. Please verify that your e-mail address is correct in your account settings." Since multiple Thunderbird e-mail accounts share a "pool" of possible SMTP servers and logins, TB will remain unusable on providers which require the sender e-mail address to match the SMTP login (unless the sending e-mail account randomly matches the corresponding SMTP server login). This appears to be a new "security measure" added by charter.net. It does not affect e-mail applications which associate a specific SMTP server and login with each e-mail account (UNLIKE Thunderbird). Is there any potential fix for this?

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You can associate each account with its corresponding smtp server. Open Tools/Account Settings, select Outgoing Server (SMTP) at the bottom left pane, then Add or Edit smtp servers for each charter account. Use mobile.charter.net on port 587, SSL/TLS security, authentication = normal password, User name = email address.

Then, select an account in the left pane of Account Settings and click the drop-down next to Outgoing Server (SMTP) in the right pane to select the correct smtp server.