I've been using Outlook 2003 for years, but after miagrating to Vista, the\nfollowing problem cropped up.\n\nWhen I try to send some emails in Outlook 2003, I get the following error\nmessage:\nTask 'Main-Sending' reported error(0x80070057) : 'Could not complete the\noperation. One or more parameter values are not valid.' (note: "Main" is\nmy primary pop3/SMTP server).\n\nMy ISP says it's Microsoft's problem, not something at the server, and they\nhave no idea.\nI searched the MS website, but did not get any hits on the error.\n\nIt only affects *some* of the emails. So far, all of the affected items\nseem to be ones that I am forwarding and have attachments or imbedded\nInternet links.\nHowever, some forwarded emails with links or attachments go through just\nfine. Usually, if I regenerate the message from scratch, it will go\nthrough.\n\nHas anyone experienced this problem and worked out a fix?\n\nThanks.