I have recently had this error when finishing my Project Server 2007 installation on an existing SharePoint 2007 server farm.
After creating the Project Web Access site (in my case using a host header), I received the following error message
“The administrator has taken this farm offline. Project Web Access is not available at this time”
The trick here is to remember to take the farm out of Quiesce mode!
- You must go to Central Administration > Operations > Quiesce Farm
- click the ‘Reset’ button
- Now try your PWA URL in a browser. The page should render after some time.
Once the site is live ‘un-Quiecsed’ the PWA should jumped into life and the two project services (Microsoft Office Project Server Queue Service and Microsoft Office Project Server Events Service)will start automatically