error 176310 on dual-purpose pins

I am getting the error- Can't place multiple pins assigned to pin location Pin_12 while compiling a Cyclone IV device. I am hoping to use the DCLK IO as an application pin and have set Device_and_Pin_Options > Dual_Purpose_Pins > DCLK = Use_as_regular_IO. Settings for configuration are Passive-Serial/Standard. Forum posts suggest this should work but I still get the error. Can anyone please help?