Simply put, is the truss above, with the displayed boundary/internal fixity conditions and distributed loading, structurally stable?
As mentioned in the comments to the question, since you are using a 3D analysis tool, you need to fix rotations around the X and Y axes. If you had been using a 2D analysis tool, simple pinned and roller supports would be suficient since rotations are only allowed around the Z axis, but since this is a 3D model, rotations around the other axes must be restrained.
@Wasabi is right. I fixed Z displacement and X and Y rotations at each and every node and it worked. The truss is structurally stable for given loading. However it is important to be careful with software assumptions and fix nodes where necessary to simulate a 2D model in a 3D program.