Samiam - 2:24 pm on Jan 16, 2013 (gmt 0)

I would greatly appreciate some advice from some more seasoned ecommerce veterans. I had a product listed on on website as on backorder and due 1/14. When the products did not arrive at our location, I contacted the manufacturer which forwarded me the tracking information that showed it would be delivered 4 days later than what they had originally told me. I notified all my customers of this delay. One customer, that placed his order on 1/13 is not happy. He felt his need to through all his titles into an email, told me it was unacceptable I WILL deliver his product or else. I apologized to him, void the authorization on his credit card and cancelled his order, logistically speaking I simple cannot ship a product I do not have. Since canceling his order I have received 6 emails, each more threatening with lawyerese than the last. Now he tells me he will be filing some type of lawsuit, there will be a "final legal resolution", because he never gave me power of attorney to cancel his order and I am obligated to deliver this item or else. I was always under the assumption I could cancel orders. Can I cancel a customer's order?