Error when scan

I am sure it scans fine but I am getting this error when I scan (without scan window open)

Exception in thread "Thread-3938" java.lang.NullPointerException
at GUI.Hacker.receivedScan(Hacker.java:707)
at View.View.addData(View.java:233)
at Assignments.PacketAssignment.execute(PacketAssignment.java:283)
at com.plink.dolphinnet.Reporter$RunAssignment.run(Reporter.java:83)
at java.lang.Thread.run(Unknown Source)