In the General Transaction Entry window, you do have the option to Back Out a Journal Entry OR Back Out a Journal Entry and Create a Correcting Journal Entry.
Transactions >> Financial >>General
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There is an icon at the top of the window called Correct
This is helpful if you simply want to back out a journal entry that has been posted.
Also helpful if someone has entered a large journal entry and posted it, but one of the accounts is incorrect; you can then back out and create a correcting entry to edit and post
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You would choose the Year and the Original Journal Entry Number
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Click OK
Once you click ok, the reversing journal entry will pop up, and you can amend (if needed) and post:
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