When you’re trying to create a Search Center site in SharePoint 2010, you get an error that looks like the following:

You have to activate SharePoint Server Publishing Infrastructure in Site Collection Features in order to create Search Center sites:

When I was configuring SharePoint 2010 in Windows 2008 R2 to use Kerberos, I bumped into this Technet article, which discusses configuration of Kerberos for SharePoint 2010.

http://technet.microsoft.com/en-us/library/ee806870.aspx

In the article, it advises to verify that Kerberos is used by looking at the Security event log and looking for Event 540. Well, event 540 never showed up. It confused the heck out of me. Apparently, event 540 is only for Windows 2003. In Windows 2008 R2, the equivalent of Event 540 is Event 4624. The following article mentions this:

http://www.endusersharepoint.com/EUSP2010/2010/04/21/life-is-just-a-bowl-of-sharepoint-%E2%80%93-part-8-installing-sharepoint-2010-beta-with-kerberos/

In case you are wondering where the ApplicationHost.config is located, perhaps because you have to make some modifications to it, you can find the file at:

C:\Windows\System32\inetsrv\config

Backup the file before you make modifications!!!