First, check the Queue log on the Team Approach server for error messages. You may see the error message "SY025" or "UL168". Both of these are general errors and will be probably followed by more detailed information.
If you did not see an error message in the log, check the upload folder for a .bad file. If accounts appear in a .bad file this means they were rejected. Sometimes you can see why, by examining the data there. Not all rejected accounts will be in the .bad file though. For rejected accounts that are in the .bad file you can look in the .log file in the upload directory for a more detailed error. You can also check the UL_Account_Messages table for a detailed error:
where process_id = <process_id >
and error_status = 'E'
order by message_text;
If there is no error message or .bad file, this means that the account was deferred because it did not meet the requirements for account creation because it had an invalid name or address. Check the UL_Account_Messages table for a detailed error.