How do I stop it from coming on when reg. Key is turn on?

Sergio silva, September 2015

It is a general error meaning you pressed the wrong button sequence. Make sure you don't use a decimal point in prices and you have the key in the correct mode. If you cannot remove the error with the clear button, it has probably lost the programming due to a faulty battery.

Registerman, September 2015

30 seconds!!!!! that was all it took fp rme to find this:

http://www.fixya.com/support/t24496529-fix_samsung_5115ii_error_e1

Which was probably less time than it took you to type your question and post it here!!!!!!

XXX, September 2015