Unplug it then plug it back in. That seem to fix most problems.
Yes, but you need to remove the 9V battery first so that the memory is cleared.
Unplug it, remove the battery - wait 10 minutes, install a new battery them plug it back in.
If the computer re-booted you will need to press quiet alarm and then reprogram your settings.
If nothing changes, you are SOL because your RainSoft system is obsolete and dealers are not working on them.