How to suppress windows system message

[Felix Antony]

I have created a application which copies files from hard disk to
Floppy drive using the CopyFile() API.
In the middle of the copy process for a large file, if the floppy is
removed from the drive then windows
system popup's up an error message.

I want to suppress this error message that is popped up by the system.
I googled and read about SetErrorMode() API used
by many applications to solve similar issues and tried using it with
all the possible flag options but it fails. Sample code -

UINT uOldErrorMode = SetErrorMode (SEM_FAILCRITICALERRORS |
SEM_NOGPFAULTERRORBOX);
::CopyFile("C:\text.dat","A:\text.dat", FALSE);
SetErrorMode (uOldErrorMode);

SetErrorMode() API fails to suppress the error message. Can anyone
help me in understanding why is it not working with for my
application?

I then came across the below link : http://support.microsoft.com/kb/128642
which talks about the key

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Windows\ErrorMode

whose value can be set to 0,1 or 2 to suppress or show the error
messages. This solution works for my application but I feel that

a. It is not a good programming practices to access the system key
directly? there should be a API that should do this.
b. Such a code shall fail the UAC when executed on Windows Vista or
Windows 7.

Can anybody please provide some help with the above issue.

Regards,
Felix

[Goran]

Perhaps SHFileOperation could help (set FOF_NOERRORUI)?

But why is it so bad to just let the system pop up the message? You
already have a person in front of the machine - who else did yank the
disk out?

Groan.