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An email will not send and I get "syntax error (#5.5.4)." What does this mean?

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  • Last reply by pumc

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I try a group mailing. I put in the group as a recipient. It gives me the error above. I am using Thunderbird with Windows 8.1.

I try a group mailing. I put in the group as a recipient. It gives me the error above. I am using Thunderbird with Windows 8.1.

Chosen solution

5.5.4 Is an invalid email address. It is a message from the mail server that Thunde4rbird relays, not a Thunderbird error.

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syntax error (#5.5.4)

Is this the entire error message?

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I ran the document through the spell check and now the group mailing seems to work. Thanks.

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Chosen Solution

5.5.4 Is an invalid email address. It is a message from the mail server that Thunde4rbird relays, not a Thunderbird error.

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I have to run the email through spell check every time I use this group. I checked all the email addresses in the group and they were fine. At least I can send out emails using the group as recipient.