Converting automatically into obj file, Even though, I have set up to convert C file into hex file

Hi everyone,

I got a problem is that I create my own circuit on Proteus, and am going to upload the hex file of Keil into the simulational processor 8051in Proteus

However, when I "Output" Hex file, in the Object file which then emerged the obj file as the picture below. Is there any way that I can export C file into Hex file? or anyway that I can fix the aforementioned error.

Thank you so much!