Upgrading from version 3.0 to 3.1 requires a complete new installation therefore this upgrade will not work with version 3.0. The cost is $25 to upgrade from 3.0 to 3.1 with a valid license and ownership of version 3.0.
PhotoGrav 3.0
Computers that do NOT have an internet connection will need to find the file with the name photograv.exe and replace it with Photograv 3.0.3. A backup of this file is recommended.
Find the files with the names photograv.exe and pgdg.dll and replace them with:
