In reply to dkumar264:
All you need is a forward type declaration. Here, the scoreboard file is getting compiled first and then the sequence item filed is compiled. So, when the scoreboard file is compiled, the compiler doesn’t know anything about sequence item class. Hence it throws an error.
Add a typedef before the scoreboard class:
typedef class seq_item;
class sboard extends uvm_scoreboard;
Moreover, it is advisable to use `include’s in a single file and not in multiple places. This will help you visualize the problem more easily.
Refer to typedef class and this forum question for more details.