Casio ES-2000 Point of Sales/Cash Register

Question

Have 3 ES-2000 POS's networked in my business. Two of them are giving me an error message "E107". I'm not sure what this error is and I haven't been able to locate it online. The company that set up the system is out of business. The system is 7 years old and other companies don't know what to do with it.