The best way since Microsft can change things whenever they want would be to bypass outlook altogether.
You should consider an SMTP component that you could use to talk directly with the mail servers and send the messages completely bypassing and mail program the user has.
SMTP Wizard is a great program for accomplishing this task and is currently used by a large number of developers all because of the new security features in Outlook.
The SMTP Wizard control supports sttachments and all the like.
http://www.seekfordsolutions.com/Products/Files/SMTPWizard/SMTPWizardv2.exeEnjoy
Brian Seekford
Seekford Solutions, Inc.http://www.SeekfordSolutions.comInternet ActiveX Controls and .NET Class Libraries.
SMTP/S FTP POP3/S HTTP/S SNTP MIME PING WHOIS TRACEROUTE NNTP DNS MX
Base64, UUEncode, yEnc, MD5, SHA1, URL, Quoted-Printable.
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