Active Directory Import Issues

I am trying to import users from Active Directory which I have done many times without issues but now I have 3 failed records that will not import.

Total Requesters in Active Directory		261
•	Added Records	0
•	Overwritten Records	258
•	Failed Records	3

How would I find out more details of what or why these accounts will not import?

OK so I found this in the system log under one of the accounts that it is not importing

java.lang.NullPointerException

Any ideas how to correct this issue.

Thanks