I am working on a pretty cool little project to add to my existing application that will check the web for updates to my program. If files on the client are older than any of the files on the web server it will allow them to automatically update them. The only problem is...

If it is copying a file that is in use (like a system dll) then I can not copy it using normal methods. I will have to use the registry method. That is fine. What I need though is to know when a file is in use so I can invoke the correct method of updating it.

TIA,
Richard