CS3 Dreamweaver licensing stopped working

After years of using Dreamweaver CS3 suddenly it decided not to open. It said Licensing for this product has stopped working and that I needed to uninstall and reinstall or contact customer support at Adobe. They refuse to help since CS3 is no longer supported.

Others have suggested using the Repair Tool but the app won't open on my computer, 3.4 Ghz Intel Core 17 iMac running Yosemite.

If I reinstall will it work? Any help would be greatly appreciated.

Jon