If you cannot provide the invoice date at this time, we can give an indication of the warranty based on the manufacturing date. Keep in mind, however, that to receive warranty you will need to provide us with the proof of purchase.
For the Warranty Policy of this unit, please check and verify if your invoice date and the production date of your unit matches. For more information, please contact BenQ Customer Care. For the contact details, please check the following link: http://www.benq.co.uk/support/call_us/