Table shows all types of algorithms that can be used with wodSmtp to encode files and message parts. BASE64 is most widely used today, and in general you should use that one. BINHEX4 is mostly used by Macintosh users. UU is an old algorithm used mostly by UNIX users. QP is used for HTML or RTF based messages. UTF8 for multibyte character encoding in Unicode.

You should use these constants with Attach and AttachText methods.