Last few days I installed SharePoint 2013 and Project Server 2013 Updates from windows update, I configured the updates successfully.
I noticed that the Readers group in the root PWA site becomes empty if any of the project managers publish a project.
Knowing that the Project Site permissions are OK, and I enabled the Project site permissions and root PWA permissions sync.
Currently I used to run
Sync-SPProjectPermissions -Url http://url/epm -SyncPWASite -Async Command to overcome this issue. but I need to check every second that or the users will get
Access Denied error when trying to access the site