My fluid domain disappears and appears to turn into the fluid object when I bake I made this scene with a fluid simulation a few days ago, but the fluid domain turned into the melt word "ICE" instead of the cube I used as the domain. Is this supposed to happen? Where is the cube domain now and how can I see or edit it again? Even after I click "load start up file" or close the blender and reopen,the domain stay that way in my next project.
Fluid Domain "Disappears" When Baked

Don't worry, that is what is supposed to happen, even though it may seem odd. When you bake a fluid simulation, the domain object visually becomes the fluid flowing and no longer is visible as the cube domain object you started with: 



But notice that if you want to see the original domain cube again, you can toggle (turn on/off) the visibility of the Fluid property of the domain by clicking on the "Display Modifier" icon (  ) next to the "Fluid" button.

Another way to see the domain object's original shape (geometry) is to set the "Viewport Display" to "Geometry" in the domain's settings:



In addition, the fluid domain cube is still intact if you want to modify it -- just switch to Edit mode and you can see and edit the cube: