Are you using same windows account to run Tableau and SAP Logon?
Hi Yongbiao Chen,
I have also encountered the same issue. As mentioned under 'Additional Information' of the below KB document from Tableau, it seems, Tableau can't connect to SAP BW using the 'SAPUILandscape.xml' file and it would need SAPLOGON.INI file to connect to SAP BW system.
I have implemented the below steps and able to successfully login to SAP BW system from Tableau.
1. create a 'SAPLOGON.INI' file with SAP BW system details. ( you can refer an existing logon.ini file as template ).
2. Set up a new environment variable 'SAPLOGON_INI_FILE' on your computer ( Control Panel --> System --> Advanced System settings --> Environment Variables --> New )
with location of 'saplogon.ini' file as 'variable value'.
3. Open Tableau and connect to SAP Netweaver BW system.
Hope this will be helpful.