If neither this document nor TEC1590682 resolves the problem, here is some troubleshooting data that could help:
Is the user administered by LDAP? Did the Windows login user name or password change?
Run the command 'msinfo32' and check for conflicting versions of SQL or ODBC drivers. Make sure there is at least 16GB of memory, which is minimum recommended by SAP.
Launch the Windows Event Viewer, look in the Application and System event logs for system, user and application changes that occurred before the problem started. Also look for errors and warnings.
See the YouTube video SAP BusinessObjects BI 4.1: Using the SAP BI Support Tool