The SF accounts that are not bound will not be able to connect with their QB Customer counterpart, so a QODBC error message will be produced and sent to the SF User identified in their InterWeave Solution. In addition, when invoices are run for this SF Account, additional error messages will be produced (there is no customer).
As a first step, please create a sub-folder in your MS Office with a rule to collect error messages.
The rule.
You may need to create - in your Contacts to support these email IDs.
This will contain all messages into a sub folder.
This is an example of an error.
  The following Error occured during the execution of the Transaction Flow SFOpp2QBInvN:
2014-04-21 14:33:01.576 IW 2.41 TS SFOpp2QBInvN ERROR   XmlsqParams.statement
[QODBC] Error: 3000 - The given object ID "" in the field "list id" is invalid.
Initial Query Start Time: 2006-06-29 09:00:00.0 Final Query Start Time: 2006-06-29 09:00:00.0
 Please take a look.
  Interweave Support.