Installation of DeviceLock Service via Group Policy fails returning "The installation source for this product is not available. Verify that the source exists and that you can access it. (1612)" error.
This error indicates Windows Installer problem accessing DeviceLock MSI distribution point.
1. Make sure to specify the full Universal Naming Convention (UNC) path to the shared folder that contains the 'DeviceLock Service.MSI' package in Software Installation. For example: \\file server\share\DeviceLock Service.msi.
2. Recommended permissions to the share or file system that holds the source files for the installation package are 'Everyone - Full access' or at least 'Everyone - Read & Execute'.
Note: Please search Microsoft Knowledge Base for information on this error and how to fix it.