This has been covered before. Remember that you can use GoogleGroups to
search the archives of one or more groups for answers.
In this case, there are two things that you have to do:
1. Figure out how to start the application (HKLM/Init is the section of the
registry).
2. Figure out whether starting a managed code application that early during
boot will actually work. Sometimes it does and sometimes it fails, either
with an exception or quietly. The only surely safe way to do it is to write
a launcher program in C/C++ (unmanaged code), which you launch from an Init
key, and have that program call your managed code, after a delay while the
OS stabilizes.
Paul T.