Author: William Gerbert 

I want to copy the SYSTEM.DAT and USER.DAT files from the Windows directory. If I 
copy them using Explorer, manually, they copy fine. But, from Delphi 4 on Windows 
95, using the CopyFile function, I get an access denied error.

Answer:

The registry files are always open, and it appears that the CopyFile API function 
doesn't use the appropriate sharing flags when it tries to copy them. This function 
should do the trick for you:


1   procedure CopyRegistryFile(const Source, Dest: string);
2   var
3     SourceStream, DestStream: TFileStream;
4   begin
5     SourceStream := TFileStream.Create(Source, fmOpenRead + fmShareDenyNone);
6     try
7       DestStream := TFileStream.Create(Dest, fmCreate);
8       try
9         DestStream.CopyFrom(SourceStream, SourceStream.Size);
10      finally
11        DestStream.Free
12      end;
13    finally
14      SourceStream.Free
15    end;
16  end;