While syncing data between BillQuick and QuickBooks, you may get a message that a BillQuick record cannot transfer to QuickBooks and to refer to the 'BQQBLog' for additional details. 
You must check the BQQBLog for additional details. Here is a way to do that:
1. To open the log, you need to find the BQQBLog text file, which is located in your BillQuick installation folder, usually at:
C:\\Program Files (x86)\BillQuick20XX (for 64-bit OS) or
C:\\Program Files\BillQuick20xx
If there are multiple log files, choose the most recent one based on the Date Modified time stamp.
2. Scroll down until you find either the date the sync failed or the most recent entry. Check the message for any specific detail.
In the above example, a payment could not transfer to QuickBooks because the invoice it was paying did not exist there. Additionally, the Linked column of Invoice Review shows that the invoice is not linked (unchecked).
When the invoice is transferred, then the related payment will sync. The BQQB Log below shows the successful transfer of data with no error messages.
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02/25/2013 BQBQClient Initialized on 2/25/2013 8:13:56 AM
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* START OF SENDING PAYMENTS
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* END OF SENDING PAYMENTS
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02/25/2013 BQBQClient Terminated on 2/25/2013 8:14:02 AM
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