I believe that MSMAPI (Or simple MAPI) is a subset of MAPI. But the error you are encountering is related to a patch from Microsoft to fix a security hole that Outlook and Outlook express had, that would allowed e-mails to be sent automatically without to user's consent. This makes the programmer's job a little more difficult, and only means that if you need to develop an e-mail system you need to avoid using techniques that use Outlook (or Outlook express) as a transport engine. There a few alternatives to this problem. There are some nice blog entries that Craig Boyd has posted a while back on different ways of sending e-mails. You can find them here http://www.sweetpotatosoftware.com/SPSBlog/. Although I think his blogs do not specify exactly which one of the techniques may cause the issue. I know that Winsock does not, as well as CDO2.x and nor does Blat.


>We have several applications that send email.
>Some use MAPI, some use MSMAPI.
>Anyone know the difference?
>
>I am doing an app now that works on my PC and several others. But with some PCs
>(on the same network) the requested email is not sent. No error message. Any
>ideas.
>
>TIA