Don't waste money on this "cleaning" tool.

The real solution is that your bank most likely changed the account ID on you. Here's what you need to do:

1. Find an old .QBO file that you know was imported successfully.

2. Open the good file in a text editor like TextMate (mac) or Notepad

3. Now open the problem file in another TextMate window.

4. Find <ACCTID> in both files. Most likely, they are different.

5. Simply copy the value for <ACCTID> from the good file, and replace that value in the problem file.
6. Save the problem file and try to import it again.

This worked for me, and I didn't see anyone else post this solution. Most likely it will fix your problem.