There can be multiple causes for this error, but in this instance the database was inaccessible due to the Windows Advanced Attributes option "Compress contents to save disk space" being checked under the file properties of the DAconfiguration.mdf file.
On a local SQL server stop the SQL Server service. Once the service is stopped, on the Desktop Authority server, navigate to C:\Program Files (x86)\Quest\Desktop Authority Manager\database (64 bit Windows) or C:\Program Files\Quest\Desktop Authority Manager\database (32 bit Windows).
Right click on the DAConfiguration database and select Properties. Select the "Advanced" tab and uncheck the “Compress contents to save disk space" option. Once the option has been unchecked restart SQL Server service. The Desktop Authority console should now be accessible.