If you can see a record in your failed accounting logs and you have manually created it in your accounting package and therefore do not want this record to re-send, go to:
Your Business > Logs > Failed Accounting Logs > Click on the tab it relates to > Click on the 'Details' link > Click 'Mark as sent'
This will not send this record.
Note: If you do this, you will also not be able to send the related record. i.e. if you mark an invoice as 'Mark as sent' Commusoft will be unable to post the related payments and credit notes (as we didn't put the invoice across, we don't know 'where' to put the payments/credits).