The conn string looks fine and works for everything else.

The error states "Failure SQL Execution resulted in following Exceptions: System.Data.SqlClient.SqlException: Column names in each table must be unique. Column name 'IsCorrect' in table 'dbo.DNN_SurveyOptions' is specified more than once." which means to me that it's connected ok, but the sql has tripped.

In any case, since it looks like the latest SQL executed ok, I'll try to use the module on a hidden tab.

That did the trick. I uninstalled version 04.00.70 of the Survey module, checked that all tables had gone from the DB, then installed. This time no errors.

Thanks for your help and patience.