Exchange 2007: An Active Directory error 0×8007203A occurred while searching for domain controllers in domain [domain name]

In my test environment, the following error occurred during the Readiness Check of my Exchange 2007 installation:

Setup encountered a problem while validating the state of Active Directory: An Active Directory error 0×8007203A occurred while searching for domain controllers in domain [domain name] : The server is not operational.

My test environment was as follows:

• One domain controller, running Windows 2003 R2 SP2, 32bit
  • Active Directory
  • DNS
  • DHCP
• One member server, running Windows 2003 R2 SP2, 32bit
  • Exchange 2007 (trying to install ;-) )

The error 0×8007203A was quite strange, because I was logged on to the domain on my member server.
I took the following steps to solve the problem:

• Check the Eventlog for errors (in my case, everything was fine)
• Make sure the member server joined the domain
• Make sure the DNS addresses are pointed to the DC
• Create a new user in Active Directory with Domain Administrator rights
• Re-join the domain (join a workgroup, reboot, and join the domain again)

The final step, seemed to solve the problem. Pretty weird, but oh well, at least I continue the testing phase :-)