Probably not related but worth a try... I also use wwipstuff and i found, as have users, as well as some people who have posted on wwThreads, that removing the user ID addressed a 502 error (sorry, not a 501 error).

I know this thread is quite old, but i thought i'd chime in w/ what i just found out. I was getting a "502 Command is locally disabled" msg. After reading Rick's reply, i commented out the "username" parm and left in the "password" parm. After the change, it started working.

o=CREATEOBJECT("wwIPStuff")
o.cMailServer="my.mailserver.com"
o.cSenderEmail="my@emailaddress.com"
o.cSenderName = "My Name"
* o.cUsername = "my@username.com"
o.cRecipient="billg@microsoft.com"
o.cPassword = "mypassword"
o.cSubject="wwIPStuff Test Message"
o.cMessage="Who said this had to be difficult?"
llResult = o.SendMail()
Wait window o.cErrorMsg
RELEASE o
o = .null.

>I created WWIPSTUFF object (from West Wind wwipstuff.vcx).
>
>The code passes values of User Name and Password to propertied .cUserName and .cPassword.
>
>But the .SendMail() method return error:
>
>

>501 Invalid Base64 data
>

>
>Any suggestions what I am missing?
>
>Thank you.