You can download editor from here http://www.geocities.com/satmeat/yourpage.html,you input the key by using the editor to open the file and selecting Viacess mode if it is a viacess file,you would then see the various provider in the file on the right, select the provider whose keys you want to change, select the key tab,you then input the new key in the key that have change or if you download Strsh viacess file there is an editor(Zeebra) included which is easy to use.
My Satellite Setup
Sony KLV26HG2 LCD TV, Humax HD-CI 2000 on a Fixed Sky/Astra/Hotbird. Cerebro Card. Infinity USB Phonix. Dragon Cam v4.1 w/Firecrypt & Loader Card.