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How to fix 4.5.3 error message

  • 3 replies
  • 2 have this problem
  • 4 views
  • Last reply by Matt

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Since new Thunderbird update in December 2014, I get error message 4.5.3, "Too many recipients" & something about not enough space on temporary server. This happens when sending bcc e-mail to my standard list of people. Number of people on list has not been increased and my outgoing server with my ISP is not the problem. What is and how can I fix it? Thanks for your help.

Since new Thunderbird update in December 2014, I get error message 4.5.3, "Too many recipients" & something about not enough space on temporary server. This happens when sending bcc e-mail to my standard list of people. Number of people on list has not been increased and my outgoing server with my ISP is not the problem. What is and how can I fix it? Thanks for your help.

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please an exact error message please.

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Actual message: The size of the message you are trying to send exceeds a temporary size limit of the server. The message was not sent; try to reduce the message size or wait some time and try again. The server responded: #4.5.3 Too many recipients.

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Ok I have see this before. The usual cause is incorrect SMTP settings. Most often settings for no password when a password is required.

So Tools menu (Alt+T) > Account settings > server settings > outgoing server (SMTP) and edit the outgoing server and ensure that a password is required.

If that off the cuff did not work, then what SMTP server do you have registered in there and what are the settings.