What the forbidden sign means in keil Project view ?

[Bill]

As the picture shows! I have changed some Option of target and some forbidden sign appears. I guass it means the file is not available,if so, how can I delete it. Why It become not available?

Why I can not add s110_nrf51_8.0.0_softdevice.hex. It would not build when I add it.

[awneil]

This is a Keil question - nothing to do with Nordic.

See the uVision documentation: www.keil.com/.../uv4_ca_filegrp_att.htm

[shibshab]

It means that the file is not used in the current target.