new project in keil using stm32f10x

hello, I'm trying to get familiar with keil, I run one of the example files on this soft to blink a led using stm32f10x and everything was ok but when I want to create a new project I get this error:

Empty.axf: Error: L6218E: Undefined symbol SystemInit (referred from startup_stm32f10x_md_vl.o).

I get this error even if I dont write any code in main, I also added stm32f10xr.lib to my project but it didn't solve the problem,

does anybody know what the problem is?
thanks in advance :)