Not able to release a sales order

[SAPSupport]

Not able to release a sales order, system shows message 'some sales orders cannot be released; check document status.'

Steps:

1. Go to the sales orders work center view.
2. Search and select the order ABC.
3. Click Action - Release, you get the error: some sales orders cannot be released; check document status.

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[SAPSupport · Accepted solution]

The sales order ABC is with status=Open, which means the order has been released already. 

To further delivery the order, the user need to release the customer demand and then it will start the delivery process of the order.