The following attachment types are supported by Microsoft Exchange:

•	Multipurpose Internet Mail Exchange (MIME) (also known as Multimedia Internet Mail Exchange) NOTE: The Microsoft Network (MSN) does not support MIME.
•	UUENCODE

To select the attachment type used for sending attachments in Internet mail, follow these steps:

1.	In Control Panel, double-click the Mail And Fax icon.
2.	Open the Internet Mail profile, click Internet Mail, and then click Properties.
3.	On the General tab, click Message Format. To use MIME format, click the Use MIME When Sending Messages check box to select it. To use UUENCODE format, clear the Use MIME When Sending Messages check box.
4.	Click OK.

MIME Details:

The MIME format has certain defined file types. To see the available file types for MIME format, follow these steps:

1.	Double-click My Computer.
2.	On the View menu, click Options.
3.	On the File Types tab, registered file types are listed in the Registered File Types box. Click each file type and check the File Type Details box to see if Content Type MIME is listed. If it is, the file type is available for MIME file attachment.

NOTE: Microsoft Exchange includes a native Internet mail connector that supports both the Request for Comment (RFC) 822 and RFC 1521 (MIME) specifications.

UUENCODE Details:

UUENCODE coding and decoding is taken care of automatically if both the sending and receiving mail programs support UUENCODE. If not, you must run a UUENCODE or UUDECODE tool to convert a non-ASCII text message. Microsoft does not supply UUENCODE or UUDECODE tools.

For information about how to obtain an RFC document, please see the following article in the Microsoft Knowledge Base: