If you are hitting connectivity issue with Tableau and DRILL with following symptoms, you are probably hitting a bug in Tableau 10.0.1/10.0.2.
 You will see following error when you try to connect Tableau 10.0.1/10.0.2 to DRILL with authentication
 No issue in connecting Tableau to non-authenticated DRILL.
 No issue with DRILL EXPLORER in connecting to either authenticated or non-authenticated DRILL.
The issue is fixed in Tableau 10.0.3.
 Try running tableau using command line with command "tableau.exe -DProtocolServerReconnect=1" and see if you are able to connect to driver. The easiest way in windows is to set the properties for a desktop shortcut by adding -DProtocolServerReconnect=1 after the double quotes pointing to the tableau.exe file.
 Second way is to make sure that when you try to connect to your driver DSN from tableau, you are not prompted with a connection dialog i.e. you set values for all the driver keys in windows registry.
The issue is observed in case user is presented with connection dialog while connecting to driver from tableau. So, the fix is to suppress this connection dialog. When we try to connect to ODBC data sources from tableau, we can either choose to connect to DSN or Driver. If connect using driver is selected, then connection dialog is always presented and connection fails for some drivers.
If we try to connect using DSN then we can suppress connection dialog by setting all connection properties in windows registry. The connection properties can be set under the registry path: HKEY_LOCAL_MACHINE\SOFTWARE\ODBC\ODBC.INI\ [Driver DSN]