Solved by ptrblck in post #2 
              
              
                The error is a shape mismatch as returned a bit higher in the stack trace: 
RuntimeError: mat1 and mat2 shapes cannot be multiplied (64x2 and 4096x4096)

This is caused because you are assigning the new nn.Sequential block to model.classifier[0] and keep all other modules from the original model.cla…