Due to previous issues in Dataverse, the Dataverse indexes could become corrupt and cause dataflows not to open or run. You will see errors such as "Sorry, something has gone wrong: An unexpected problem has caused the application to stop working properly. Unable to retrieve the data flow top level element corresponding to the execution-session."
Other times, the error may be in the same format, but the dark error message will be, "null null".
- Stop Dataverse by selecting "Stop Dataverse" from the Windows Start Menu. Check to ensure that there are no java.exe processes running per the directions here.
- Locate the following directory and rename it to something like
indexes_old_3.0.5. This will force the indexes to be rebuilt when Dataverse is restarted later.
- Restart Dataverse by selecting "Start Dataverse" from the Windows Start Menu.