A virtual server includes at least one processor to retrieve a user layer from a user's personalization container, and initiate mounting of the user layer to a target operating system. During the mounting, the at least one processor determines that the user layer did not originate with the target operating system. The user layer is modified so that file system objects and registry objects are compatible with the target operating system. Mounting of the modified user layer is completed to create a single composited layered image.