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Error message 'Header size exceeds fixed maximum size'?

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I'm trying to send an email to a group of addressees, which I use frequently with no problems. I am sending a one page attachment which is not large. Every time I try and send it I get the error message, 'Header size exceeds fixed maximum size. Please check the message and try again.' I'm afraid I have no idea what this means.

I'm trying to send an email to a group of addressees, which I use frequently with no problems. I am sending a one page attachment which is not large. Every time I try and send it I get the error message, 'Header size exceeds fixed maximum size. Please check the message and try again.' I'm afraid I have no idea what this means.

Asịsa ahọpụtara

Talk to your email provider or reduce the number of recipients.

Gụọ azịza a na nghọta 👍 2

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Asịsa Ahọpụtara

Talk to your email provider or reduce the number of recipients.

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Thank you so much for your help. I reduced the number of recipients by 5 and the message has now sent. However, I'm still puzzled as to why it's suddenly decided that there were too many recipients when I've been using that same list for many months now. Thanks again.