My 444 sink erator was experiencing the same issues. Not having the manual (as I didn't originally purchase the device), this website thread helped me solve the issue.
Simple steps:
1) Press red reset button on bottom of device
2) Use a 1/4 allen wrench and turn back and forth (I went +/-45 degrees a couple of times)
3) While running some water through, turn on the unit.
The beauty of the internet -- fixed within two minutes of having the issue. Thanks for the help.
jim
May 2012