Thread: SystemParametersInfo set wallpaper issues

The third parameter of SystemParametersInfo is supposed to be a null terminated string containing the path to a file to set as the desktop background.

If I wanted to just set it as the null background then this works:

Code:

SystemParametersInfo
	(
	 SPI_SETDESKWALLPAPER,
	 0,
	 "",
	 SPIF_SENDCHANGE
	);

But when I try to set the background to a file this doesn't work. GetLastError returns ERROR_FILE_NOT_FOUND even though that's the correct path to the file.

Code:

SystemParametersInfo
	(
	 SPI_SETDESKWALLPAPER,
	 0,
	 "H:\nn.bmp",
	 SPIF_SENDCHANGE
	);

Even stranger when I try calling and outputting SystemParametersInfo with SPI_GETDESKWALLPAPER I get a jumbled string that looks something like 78BB5654 (so it's random looking but it's the same every time).

How can I set the desktop wallpaper? Am I formatting the path wrong?