SharePoint and SQL Server Express
Stumbled across a little gotcha during a SharePoint installation the other day. It actually happened whilst creating a SharePoint Portal Server 2003 set-up, but the database software was the problem.
The set-up was a single server install running Windows Server 2003 with Active Directory (i.e. as a domain controller). The next step was to install SQL Server 2005 Express Edition. Then came installing SharePoint...
...the SharePoint installation appeared to be fine until it came to trying to create the first portal. The configuration wizard failed... and failed again... and again.... stopping at various % levels (anywhere from 41% complete to 99% complete)
Several Google searches later, I finally came across a snippet from Microsoft stating that running SQL Server 20005 Express Edition on a domain controller was not recommended. A separate blog post started talking about checking if protocols were enabled for SQL. Delving in the SQL Server config tool, and sure enough, all protocols had been disabled. Enabling TCP/IP solved the problem - portal created first time.
Sooo, if you are running SQL Server 2005 Express Edition for a web application, and are having difficulties, check that SQL Server hasn't disabled protocols (TCP/IP and Named Pipes being the likely candidates).