I am currently trying to change my desktop background using SystemParametersInfo() vs doesnt give me any errors when I type my stuff in but when I run the program I get this
A better description of the error would definitely help more. For starters though, you should replace all of the forward slashes with double black slashes "\\".
SystemParametersInfo(SPI_SETDESKWALLPAPER, 0, "C:\\Windows\\Downloaded Program Files\\Flowers.jpg", SPIF_UPDATEINIFILE);
That looks right, however there's no telling what the actual cause of the error is without a little more information. Also a PDB file does not affect a program, that's for debugging a file.