Deleting a Credit Memo throws an error: Deleting [Voiding] a Credit Memo that has been refunded is not permitted.
1. Edit the Credit Memo
2. Navigate to Items tab > Apply sub tab > unapply the Credit Memo from the Refund
3. Click Save.
4. Edit the Credit Memo again.
5. Hover mouse over Actions > select Delete
Or click Void button if user wants to void it. If Void button is missing, please navigate to Setup > Accounting > Accounting Preferences > General Tab > Void Transactions Using Reversing Journals = F