The user account specified as site owner for the web application used by the Project Web App site is employed by Project Financial Server for a wide variety of internal operations involving the PSI.

The site owner user account requires Log On permission in the Project Server. Disabling the Project Server user corresponding to the site owner, or denying it Log On rights, will cause actions in the Project Financial Server administration pages and web parts to fail with the following error:

Value cannot be null. Parameter name: context

If, for various reasons, the site owner user account of the PWA site is disabled at Active Directory level, to continue using Project Financial Server, you must change the site owner to a new user with proper permissions. You can do this using the PowerShell script below.

$site = new-object Microsoft.SharePoint.SPSite(“http://<servername>/<ProjectServerName>”)
$web = $site.OpenWeb()
$newOwner = $web.AllUsers.Item(“<new-owner-username>”)
$site.Owner = $newOwner