If you are getting the “Your process does not have access rights to this namespace” error after switching your WCF service to run under a different account, try the following:
1) Install the Windows support tools from your Windows 2003 Server install CD from SUPPORT/TOOLS.
2) Open a command prompt and go to C:\Program Files\Support Tools
3) Run the following:
httpcfg set urlacl -u http://+:
That crazy ACL string at the end is in SDDL syntax and I found this great reference for SDDL from the University of Washington’s website: http://www.washington.edu/computing/support/windows/UWdomains/SDDL.html