How can I license my Word, Excel or Access add-ins?
We have many customers that use Instant Protection PLUS 3 (IPP3) or Protection PLUS 5 SDK to license their Microsoft Office add-ins.
The easiest approach is to use the IPP3 DLL interface. We have created a tutorial that walks you through a sample for Excel or Access:
- Microsoft Office applications, such as Word and Excel, have a sophisticated macro programming language that can call Protection PLUS functions. However, because many viruses have been spread through this macro programming language, the user can choose whether or not macros should be enabled. If the user chooses to disable macros, your security checks will not run either. The only way to protect your document is to force the security macro to execute before they can view the file.
- If you are selling Excel formulas, consider packaging them as an Excel Add-In. In this case, the security calls can be verified before the add-in is loaded and the functions become available to the user.
- If you want to apply code protection to both the licensing code as well as your own code, you could use a solution such as the DoneEx VBA Compiler for Excel. This has a setting to "Make VBA unviewable" and will help prevent users from accessing, copying, or altering your VBA code. We have tested this with our Instant Protection PLUS 3 DLL and did not have any issues.
- When Microsoft Office is installed via a Click-to-Run deployment, your customers may experience issues with Microsoft Office add-ins or macros that use Protection PLUS features that write values to certain areas of the Windows Registry. This can occur even if you properly set the permissions for the values written to the Windows Registry. Read this article for more information. When using Instant Protection PLUS 3, you need to set the license file location to "Auto-create in the current user registry".