use strict;
use warnings;

use Win32::OLE;
use Win32::OLE::Variant;

use constant CLSID_ACTIVEDESKTOP   => '{75048700-EF1F-11D0-9888-006097DEACF9}';
my $actdesktop = Win32::OLE->new(CLSID_ACTIVEDESKTOP) or die();
$actdesktop->SetWallpaper('C:\WINNT\winnt256.bmp');

##</code><code>##

C:\>"C:\Documents and Settings\blm\Desktop\test1212.pl"
Win32::OLE(0.1501) error 0x80004002: "No such interface supported" at C:\Documen
ts and Settings\blm\Desktop\test1212.pl line 8
        eval {...} called at C:\Documents and Settings\blm\Desktop\test1212.pl l
ine 8
Died at C:\Documents and Settings\blm\Desktop\test1212.pl line 8.

C:\>

##</code><code>##

STDMETHODIMP CMyDesktop::SetWallpaper(BSTR bstrPath)
{
	HRESULT hr;
	IActiveDesktop *pActiveDesktop;

    CoInitialize(NULL);
	//Create an instance of the Active Desktop
	hr = CoCreateInstance(CLSID_ActiveDesktop, NULL, CLSCTX_INPROC_SERVER,
						IID_IActiveDesktop, (void**)&pActiveDesktop);
	
    hr = pActiveDesktop->SetWallpaper(bstrPath, 0);
	if (hr != S_OK) {
        goto error;
	}
	hr = pActiveDesktop->ApplyChanges(AD_APPLY_ALL);

	pActiveDesktop->Release();

	return S_OK;
error:
	return hr;
}

##</code><code>##

use strict;
use warnings;

use Win32::OLE;
use Win32::OLE::Variant;

my $adtest = Win32::OLE->new('damnit.MyDesktop') or die();
$adtest->SetWallpaper('C:\WINNT\winnt256.bmp');