Hi Jan,just get a straight screwdriver in each of the 2 lower slots and twist.It is only an inspection cover so even if it is left off,there is no harm.Is the machine not working correctly?Bleeping and error lights on?
Turn off the power at the plug,take off the panel and see if there is water in there.Once you drain with a sponge,it will reset.You may have a sump leak if it refills and these are hit and miss to cure.All the best.
Foxy
July 2008