Please make sure that you always have the latest version of SDM.
This is not only recommended but required since future versions of the SDM catalog may not be readable by an older version of SDM. Also, using the latest version of SDM ensures that you have the latest features, enhancements and bug fixes. Although SDM attempts to check for new versions at the beginning of each session, it might not always be successful downloading it.
As of February 01, 2016, the latest version of SDM is 18.104.22.168.
To verify which version of SDM is current installed manually on your computer, please select “Help" from the main menu and then select “About” from the submenu. The About dialog box will display the SDM version.