Email won't send
Thunderbird won't send an email because it thinks the email address I'm sending to has spam features. When I type the email address in the To bar it immediately puts an asterisk after the address. The email address is bzawacki@xxxxxxx.com. When I send the email it looks as though it sends then immediately an error message comes up that says the mail server responded with error code 43TH9mcn085202 and blocked the email because it has spam features. All I'm doing is sending an insurance estimate as an attachment to my car dealer. I've gone out to my ISP and added this address as a trusted sender but that didn't fix my issue.
Wšykne wótegrona (1)
an error message comes up that says the mail server responded with error code 43TH9mcn085202 and blocked the email
As you stated, the error comes from your email provider's server, not Thunderbird. You'll have to talk to your email provider about why they think your message is spam.
As a workaround you may want to try sending the message via webmail.
Musyśo se pla swójogo konta pśizjawiś, aby na pśinoski wótegronił. Pšosym stajśo pšašanje, jolic hyšći njamaśo wužywaŕske konto.