When you buy our books, your purchase is covered by our 10-day money-back guarantee. If you are, for any reason, not entirely happy with your purchase, we will cheerfully issue a full refund. We develop and sell software that we use ourselves every day and have thousands of satisfied customers worldwide, and our support is second to none. That is why we can afford to back our products with this special guarantee if any damage condition of book or page missing book then we send books of our own cost but defective copy must be returned. To request a refund, simply contact us with your purchase details within ninety (7) days of your purchase. Please include your order number (sent to you via email after ordering) and optionally tell us why you’re requesting a refund – we take customer feedback very seriously and use it to constantly improve our products and quality of service. Refunds are not being provided for services delivered in full such as installation service and provided knowledge base hosting service. Refunds are being processed within 21 days period.