Could you please define what you mean by 'duplicate'? Do you mean that the same order or invoice number exists twice when you look at the order or invoice screens? Or perhaps when you print these documents, you are getting 2 copies instead of 1? Or perhaps you see the same invoice in both the current or history files at the same time?

To answer the above specific questions very quickly:

1) The would be the result of data corruption, often due to incorrect network settings.

2) Either the specification or the printer driver is set to print two copies.

3) This is the way version 6.8B works, to allow easier reporting off of the History file.
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