I'm interested i know how many Members running or admister a Mail-Server in house.

Which OS you're using and which application? Which AV software?

Also which are the most common problems.

I running several Mail-Server on MS-Windows Server 2003 Web-Edition. The Mail Server Application I using are mainly 2:Kerio and IS Mail. On Kerio Mail Server I use Avast for Kerio as AV software and for IS Mail I use ClamAV.

Kerio Mail Server has a better graphical Interface as IS Mail but has one Disadvantage: All incoming mails are stored as .eml files which you can just open with any e-mail client and without the need of an mail account if you've acces to the server and can copy the files!

IS Mail is different. There isn't a graphical Interface but easy to setup. The mail are stored in one file, for example all incoming in a file named Inbox (without extension) and so on. If you dont have an mail account you can't open any mail's. So it's more secure!

Whats your experiences?

I'm running a standard sendmail/pop3 linux server using Slackware 10.1. Webmail portion I'm using SquirrelMail with Apache SSL. For spam/virus I'm using SpamAssassin with Clam-AV as virus front end scanner integrated using MailScanner. All quite secure, users can only access their own mail boxes which are separate protected file areas. For tighter security, pop3 is only available on the Intranet (inside the firewall) and International roamers come in through the secure web mail.

I run a mail server on windows 2003 server, it's actually lansuite 2004, Mcafee webshield smpt does the virus scanning, the lansuite will also forward mail to an exchange server I have running as well.

The nice thing about lansuite is it's wap module, which enables me to use it with any wap enabled phone. And of course no pop 3 over the internet as previous poster, not a very good idea. Webmail is SSL secured.

I run an exchange server 2007 on windows server 2003 with GFI MailEssentials for spam protection. I also run CentOS 5 + Postfix as smarthosts to forward mails through.

Exchange Server is a real memory eater, you need at least a machine with 2gb of ram (i had it on a 1gb of ram+core 2 before, and it was really slow!). GFI MailEssentials run on the SMTP gateway (the ISA firewall machine).

My overall experience has been positive, I haven't had dramatic downtimes, and outlook web access and remote activesync works like a charm on my Nokia N73 with the exchange addon from Nokia.