User Agent: Mozilla/5.0 (Windows NT 5.1; rv:20.0) Gecko/20121203 Firefox/20.0 Build ID: 20121203161707 Steps to reproduce: Create a new news message or reply to an old one. Then try to send message. BuildID: 20121214193457 Actual results: Error dialog does appear with message: "Sending of message failed. Please verify that your Mail & Newsgroups account settings are correct and try again." Error Console: Error: GenericSendMessage FAILED: [Exception... "Component returned failure code: 0x80004002 (NS_NOINTERFACE) [nsIMsgCompose.SendMsg]" nsresult: "0x80004002 (NS_NOINTERFACE)" location: "JS frame :: chrome://messenger/content/messengercompose/MsgComposeCommands.js :: GenericSendMessage :: line 2909" data: no] Source File: chrome://messenger/content/messengercompose/MsgComposeCommands.js Line: 2912 With BuildID=20121211204728 the same settings work fine. Expected results: Message should be sent.