1. A method for patching a virtualized application, comprising: storing a current version of a virtual application image at a first location; wherein the virtual application image captures setup-time changes and run-time changes made to a computing device by a virtualized application; wherein the virtual application image is segmented into blocks; accessing a current mapping file from the first location; determining changes to a client virtual application image by comparing the current mapping file to a client mapping file; obtaining the changes from the current version of the virtual application image at the first location; and updating the client version of the client virtual application image using the obtained changes and any portion of the client virtual application image that did not change.