As mentioned by David there is a known issue within the array configuration script that provides a false error message about SSL. Until this issue is fixed we have had the most success temporarily turning off SSL on REST to allow the script to run and then turning it back on.
Also know that it talks to the primary service (decoder, concentrator, archiver) and the appliance service. This means you would need to make sure that the REST SSL/Non-SSL option is set the same for both services or you will receive the same error message. If you go into Explore view on the service (decoder, concentrator, archiver) you set the REST SSL option under the REST folder node. To set it correctly for the appliance service you have to go down to the deviceappliance node at the bottom of the Explore view and then look for another REST folder node. Inside there is where you find the appliance's REST SSL/Non-SSL option. Once both REST options are set the same you should have no issues.
When you are done you can go back and turn SSL back on if you use the REST interface and want it encrypted again.