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You must fill in all the required fields to post the invoice.
Manual Post: You have the option to use the normal fb60 transaction if you prefer to use it to post the invoice.
Show XML: With this button you will be able to see the XML of the invoice.
Save: You must press this button to save the document.
Simulate: You can use this button to simulate the posting and check if there is some mistake remaining before doing the posting.
Post Document: You must press this button and the posting will be made. It is important to know that the correct order is first the Save button and afther that the Post Document button.
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