Hi my name isXXXXX will try and help you with your issue.
This only started to happen after you replaced the garbage disposal is that correct?
Did you remove the knockout from the dishwasher drain port?
Sometimes people forget to do that on a new installation
Not sure, will check, can't believe that could be it but probably is.
I am talking about the knockout that is on the disposer that the dishwasher drain hooks up to
It's actually quite common
I use a nut driver or big scre driver and a hammer to knock it out
Thats it - what do you expect from a builder, Thanks Tim.
Hey plumbers do it to and appliance technicians we are all guilty of it
Your welcome have a great weekend
Thanks again - wife will be happy.