Abstract: The description is directed to systems and methods for restoring a program state retained from a prior execution session on a virtual machine. On receiving a request to execute a program an image of user-independent files are mounted to a virtual machine. Specified user-modifiable files are copied from a particular user storage location to put the program in a condition to execute the program so that it begins from the previously-existing program state. During the session at least some of the files are modified and on a session end the user-modifiable files are saved to the particular user storage location to retain the updated program state.