I have a client who has a hosted Exchange 2003 server that has run perfect for several years.
In the past few weeks the server has come to a crawl at various times. After several days of research and repeated questioning of the client I finally found out that one of the PCs has been replaced with a Mac running Entourage 2004. All clients connect via RPC over HTTP. When the Mac is connect the server will start to slow down.
The server is a Dell PowerEdge 1800 XEON dual core with 2 GB ram and RAID 5 for the Exchange store and a RAID 1 for the logs. The store array will run non-stop for hours on end when the Mac connects. The CPU and RAM are at 5% and 1GB usage respectively.
I have seen where Spotlight can cause some issues like this and the end-user has turned it off (at least that is what I'm told). This has not fixed the issue.
I know that it has to be the Mac because the problems started when it came on board. I have asked if there have been any other changes that I need to be aware of and there are none to my knowledge.
I have spoken with Microsoft and they can't find anything.