I remarked that Firefox 4 is sometimes unable to send mails. What is the reason for this defect?
After having written an eMail and an attachment, I press the button for sebding the eMail. Then an information appears that the datas are loaded. Afterwards it takes some minutes till the eMail is sent or often not sent.
Alla svar (1)
Firefox doesn't do email, it's a web browser.
If you are using Firefox to access your mail, you are using "web-mail". You need to seek support from your service provider or a forum for that service.
If your problem is with Mozilla Thunderbird, see this forum for support.
http://www.mozillamessaging.com/en-US/support/
or this one
http://forums.mozillazine.org/viewforum.php?f=39
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