Michel writes: > In Enterprise networks using GroupWise or Notes > or Exchange, a good 80% to 100% of the clients are > using the client software that pairs with the > server software. So there is a GroupWise client, > a Notes client and there used to be an Exchange > client but now everyone uses Outlook. True. This is why these fancy mail systems work so well in enterprise environments. It's a lot more homogenous and controlled than the wide-open Internet. > This is the setup that the helpdesk can support. Yes. Some of these client programs are able to access "non-native" servers (i.e., Exchange from a Notes client, etc., although I don't remember the possible combinations), but it gets very ugly, very fast, and most support organizations will not support such configurations--and neither will vendors. > Although it might appear surprising, these other 10% > or 20% of users that don't use the native client that > came with the server software (for example, a Unix machine > on an Exchange server, a Macintosh on a Notes server, or > a user loosely related to the Enterprise located in the > middle of nowhere) don't use IMAP but do use POP3, and > I think it has to do mostly with IT not wanting to support > fancy configurations and yes MAPI is fancy compared to POP3. Quite so. As soon as the environment starts to get a bit mixed up, combinations and permutations multiply alarmingly, and it becomes impossible to reliably support anything. Thus, whenever two disparate systems must communicate, the safest path is the lowest common denominator ... the simplest protocol. So a non-Outlook client accessing an Exchange server will do so most reliably using SMTP and POP3, not IMAP or native MAPI or anything. > There are indeed some enterprises that have a Unix-based > mail system accessed by the crowd of Windows clients ... And one of them was Microsoft itself, until it migrated to Exchange. It's previous worldwide corporate e-mail system used Microsoft Mail clients, but a proprietary Xenix-based MTA, instead of the MS-DOS-based MTA that the company actually sold to customers. The heat that Microsoft received from its customer base due to this obvious hypocrisy was a major motivator to move the entire corporate user base to Exchange as soon as Exchange worked with some degree of reliability.