MES for Process Manufacturing - Operator Workbench 'Select' button disabled

Hi,

I created and released a batch with 'process instructions' enabled.  Logged into MES Administrator > Operator Workench.

I queried my batch and the result populated successfully. In order to lock before executing the batch in MES, I try to 'select' the line. But, the select check box is disabled/grayed out.  I logged through 'MES Process Manufacturing Administrator' responsibility. Still it is not working. Any thoughts would be appreciated.

Thanks

Suresh