I moved to a house that has a treif dishwasher. IS there any way to casherize it? It has not been used for at least 7 months. My husband says we should just change the racks but I refuse doing that. Thank you.

The best is to change the racks. If you cannot one can Kasher them in boiling water and soup at a higher temperature than the dishwasher can reach. Rabbi Yitzchak Grinblat