A computing system comprising: a client comprising a virtual environment and a non-virtual system environment; a server configured to stream an application install package, wherein the server is configured to stream the install package to the client as a series of streamlets; wherein responsive to a request to install said application in the virtual environment, the client is configured to: start an installer component in a suspended state in the non-virtual system environment, wherein the installer component can be registered in different environments and is configured to extract data from a streamlet and issue a write request to write the data into the virtual environment, wherein the write request is detected by a driver outside the virtual environment; register the installer component in the virtual environment; and resume execution of the installer component in the virtual environment; wherein subsequent to resuming execution, the installer component is configured to: begin installation of the application in the virtual environment; and initiate an attempt to perform an action configured to affect a file system or registry of the non-virtual system environment; wherein in response to detecting said attempt, a virtualization manager on the client is configured to redirect said action so that it affects the virtual environment instead of the non-virtual system environment wherein subsequent to installing the application in the virtual environment the client is configured to unregister the installer component from the virtual environment and register the installer component in the non-virtual system environment. a client comprising a virtual environment and a non-virtual system environment; a server configured to stream an application install package, wherein the server is configured to stream the install package to the client as a series of streamlets; wherein responsive to a request to install said application in the virtual environment, the client is configured to: start an installer component in a suspended state in the non-virtual system environment, wherein the installer component can be registered in different environments and is configured to extract data from a streamlet and issue a write request to write the data into the virtual environment, wherein the write request is detected by a driver outside the virtual environment; register the installer component in the virtual environment; and resume execution of the installer component in the virtual environment; start an installer component in a suspended state in the non-virtual system environment, wherein the installer component can be registered in different environments and is configured to extract data from a streamlet and issue a write request to write the data into the virtual environment, wherein the write request is detected by a driver outside the virtual environment; register the installer component in the virtual environment; and resume execution of the installer component in the virtual environment; wherein subsequent to resuming execution, the installer component is configured to: begin installation of the application in the virtual environment; and initiate an attempt to perform an action configured to affect a file system or registry of the non-virtual system environment; wherein in response to detecting said attempt, a virtualization manager on the client is configured to redirect said action so that it affects the virtual environment instead of the non-virtual system environment begin installation of the application in the virtual environment; and initiate an attempt to perform an action configured to affect a file system or registry of the non-virtual system environment; wherein in response to detecting said attempt, a virtualization manager on the client is configured to redirect said action so that it affects the virtual environment instead of the non-virtual system environment wherein subsequent to installing the application in the virtual environment the client is configured to unregister the installer component from the virtual environment and register the installer component in the non-virtual system environment.