If you forget the IP address of your HI 6600 unit, you have three choices:
1. Hook up a display to allow you to enter into the communications setup menu and see what the IP address settings are.
2. Insert a USB stick(32GB or smaller) with a Restore.txt file on it. When the unit powers up, it will look for a restore file and will set the parameters from the Restore file into the unit. This would allow you to set up a known IP address on the USB stick to download into the unit. Once you have this done, you should be able to get online and make any further changes you may wish to make. This restore.txt file would need to be in a directory named HI6600. This directory would be in the root directory on the USB stick. See attached for an example of the contents of the restore.txt file. You may make changes to the IP address in the file to meet your needs.
To use the file;
Create the directory on the USB stick, either HI6600;
Save the restore.txt file to this directory;
Insert the USB stick into the HI 6600;
Cycle power on the unit;
Once the unit powers up, use the IP address as set in the restore file to access the unit and make any needed changes.
3. Send the unit to the Hardy factory to have them determine the IP address or to reset it to a known address.
Once you get online with the unit, you should record the IP address somewhere to allow easy access to it in the future.