SourceGear DiffMerge has been the leading diff and merge tool for professional developers since 2007. SourceGear DiffMerge is licensed for use free of charge. However, to help fund new feature development and ongoing product maintenance, SourceGear asks DiffMerge users to register the product for a small fee and receive a registration key. Registration keys do not expire and can be used on every computer a user has. Registered users have access to all product updates and support, and no longer see the Register Dialog when DiffMerge is launched.
To open the Registration Dialog, select Tools | Registration... from the main DiffMerge menu. If you have already have a registration key it will be displayed in the dialog and 'valid' will be enabled. If you do not have a key or enter an invalid key, 'valid' will appear gray.
When you register DiffMerge, you will receive an email containining your registration key. Copy the registration key from the email and paste it into the Registration Dialog and then press OK to correctly configure your registration key in DiffMerge.
To remove your registration from this installation of DiffMerge, simply erase the contents of the Registration Key field in the Registration Dialog and press OK.
If you have not registered and configured your registration key, DiffMerge will occasionally prompt you with the Register Dialog. You can also force the dialog to appear by selecting Tools | Register... from the main menu.
The Register Dialog contains instructions for registering DiffMerge and obtaining a registration key and will also display any promotional materials and product offers.