Help Can't get Device Administrator back

[Jenn2006]

Hello. I was just installing the Avast security App on my phone (Samsung Galaxy S3 through Sprint), I accidentally de-activated the Device Administrator, "com.sec.sprextension.phone" and there is no option to activate it again.

How important is this? Sprint recommended we re-set to factory settings but I don't want to do this and lose all of my info unless it's absolutely necessary.

Does anyone know how to get this back? If I can't get it back on my phone is that okay?

thanks!