This site will have limited functionality while we undergo maintenance to improve your experience. If an article doesn't solve your issue and you want to ask a question, we have our support community waiting to help you at @FirefoxSupport on Twitter and/r/firefox on Reddit.

Search Support

Avoid support scams. We will never ask you to call or text a phone number or share personal information. Please report suspicious activity using the “Report Abuse” option.

Learn More

Wannan tattunawa ta zama daɗaɗɗiya. Yi sabuwar tambaya idan ka na bukatar taimako.

How to fix 4.5.3 error message

  • 3 amsoshi
  • 2 sa na da wannan matsala
  • 4 views
  • Amsa ta ƙarshe daga Matt

more options

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.

All Replies (3)

more options

please an exact error message please.

more options

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.

more options

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.