I’ve used the POP3 Connector for Exchange which comes with Small Business Server since SBS version 4.0 (NT 4, Exchange 5.0). The main limitation I’ve always bumped into was the fact that the POP Connector will check mail only as frequently as every 15 minutes.
While this is normally acceptable, if a user is anxiously awaiting an email, or, as has frequently happened to me, you’re on the phone with someone and they email you a file so you can collaborate with them on it, waiting up to 15 minutes for the file can be a real time-waster.
The second issue, which I’ve never personally cared about, was the inability to leave an email which was downloaded on the server for a period of time. Many of my clients do this as a backup option (in case something gets corrupted or deleted after being downloaded), or as a poor substitute for IMAP, to allow them to receive their mail on multiple computers. Of course, given that they have an Exchange server, this is relatively pointless, but I digress.
Last week, I found the main reason why the POP Connector for Microsoft Exchange should be avoided at all costs. It is summarized in the following Microsoft Knowledgebase article: http://support.microsoft.com/kb/842293/
SYMPTOMS
When the Microsoft Windows Small Business Server (SBS) 2003 Connector for POP3 Mailboxes component downloads e-mail messages from an Internet Service Provider (ISP) all the following symptoms may occur:
| ? | E-mail messages that are downloaded by the SBS 2003 Connector for POP3 Mailboxes are not successfully delivered to the intended recipients. |
| ? | The Microsoft Exchange 2003 Server-based computer removes the e-mail messages that it was not able to deliver. |
| ? | The senders of these e-mail messages do not receive non-delivery reports from the Exchange 2003 Server-based computer as they typically do if their e-mail messages do not reach the intended recipients. |
To summarize, the POP Connector gets the message, determines that it doesn’t know what to do with the message, and silently throws it away.
Without any warning to the user. Or the server administrator. Or the sender of the original message.
Who was the rocket scientist who came up with this plan of action?!
I’ve been using IGetMail from the folks at Lockstep. It costs $69, and has a free trial. The program allows you to customize the polling schedule to your liking (including poll freqencies of less than every 15 minutes!). It also has more flexible handling of emails than the built in POP Connector, and can be configured to simply delete emails that are corrupted on the server. This feature has saved my clients a lot of troubleshooting time, especially in cases when certain Asian-language spam or a corrupted attachment has managed to really confuse the client and server, which would have caused a client to be unable to receive any email in the past.
If you’re using POP to pull your mail down to an Exchange server, I highly recommend IGetMail as an alternative to the built in POP Connector.