i can use the copyfile(); function to copy a file to c:/windows/system32 on windows xp but then i use the function on windows 7 i cant copy it:o the file wont come there....
i had the same proble开发者_如何学Cm with writing and reading registery but fixed it by declaring a WOW key $0100 ...
i think the problem is uac but not sure.. could somebody explain me that:D?
That is indeed because of UAC. It is called File/Folder or Registry Virtualization. It is done for legacy applications who don't yet respect the new UAC rules (e.g. not writing in system folders unless you are an administrator).
By creating a manifest file you switch off this virtualization. See here. This can be a seperate file or be embedded into the exe. Newer Delphi versions already generate executables containing such a manifest and have requestedExecutionLevel set to asInvoker. This normally does not allow writing in those locations, unless users specifically run your program as an administrator. Setting it to requireAdministrator does allow writing in those locations, but also means users have to confirm they want to run your program as an administrator.
It's indeed UAC that's preventing you from copying files to the system32 folder. You have to ask yourself why you want to copy files there. A normal application should never copy files to the system32 folder.
Sometimes during install you might want to copy dll's there, but even that is legacy behaviour. Should you really want to copy files there, you should request Elevation at the start of the application.
Why are you copying files there? It should be treatead as the OS private directory. Unless you're installing a driver or the like, you should never write there. In XP you can only because you're running with Administrator privileges, try to use a plain user and you can't as well (since at least 2000, if not in NT already), but it will give you an error because it won't redirect the write. Unless you have a truly good reason to write there, I'd suggest to redesign your application to write in the proper place, instead of trying to find a way to write there. Anyway, it will fail anytime the user don't have the privileges and can't perform an elevation.
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