AspMail

AspMail allows you to send mail using the standard SMTP protocol from any program that can use ActiveX/OLE components. Features include: SMTP (sending) Messages, Multiple File Attachments, File attachments support MIME and UUEncoding, US Ascii and ISO-8859-1 character sets, PGP, Subject line encoding for 8bit message subjects, Redundant SMTP servers (If the primary SMTP server is down, the secondary server is used), Special Header Support (Standard X-Priority headers, MS Mail (including Exchange) priority headers, Urgent header, ConfirmReading and ReturnReceipt Headers), and Multiple concurrent users (Tested with 15 concurrent connections).