Unless you have DraftSight 2017 SP1 or download the HotFix, an expired certificate on Windows 32 & 64-bit computers may cause versions 2012 through 2017 SP0 to stop working (May receive the Windows message 'DraftSight has stopped working').
For hotfix or 2017 SP1 download from Dassault Systemes:
I bought the Professional version Nov. 30, 2016, and ran the "hotfix" Feb 26, 2017. It did not work! I am up to date with Windows 10.
To date Mar. 19, 2017 Dassault systems has not responded to my problem.
I will try the "fixes" mentioned in other community responses, but it is disappointing that Dassault has not published a fix to the problem they caused.