System Connection

Dear experts..

Regarding the ESS buissness package i have created a system with the aliases required and created a role assigned the Employee Self Service Workset to this role and i created a user mapped it to that role and mapped that user to the system i created earlier

the system works when i use it from an iview where i created the system but when i log on as an employee

i get the toolbar of the application but the iviews display the following error

Portal Runtime Error

An exception occurred while processing a request for :

iView : N/A

Component Name : N/A

Unable to lookup System 'SAP_R3_HumanResources'. Please check the system object and the alias..

See the details for the exception ID in the log file.

Please advice