Is there something like a redirector such as %SYSTEMROOT% that is automatically put in by a u3 drive?
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All programs must be specifically adapted for U3. Any writes to the registry or the %APPDATA% or %USERPROFILE% directory must be handled within the U3 app.
U3 makes available certain specialized environment variables like %U3_DEVICE_EXEC%, but in practice, these don't make converting an app any easier than just working within a single directory like the portable apps due.
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