Hello. STM32cubeMX v.5.3.0 Generating project as Other Toolchains (GPDSC). The project file is why the prescribed non-existing files .

[LKham]

<file category="sourceAsm" condition="ARM Toolchain" name="Drivers\CMSIS\Device\ST\STM32F4xx\Source\Templates\arm\startup_stm32f407xx.s"/>

       <file category="sourceAsm" condition="IAR Toolchain" name="Drivers\CMSIS\Device\ST\STM32F4xx\Source\Templates\iar\startup_stm32f407xx.s"/>

       <file category="sourceAsm" condition="GCC Toolchain" name="Drivers\CMSIS\Device\ST\STM32F4xx\Source\Templates\gcc\startup_stm32f407xx.s"/>

[Tesla DeLorean]

I think they exist in the HAL/CubeF4 directories trees, the tool perhaps isn't copying them into the duplicative project tree.

Unfortunately ST has no thoroughness when testing software tools.

#PlaysForSure

[LKham]

Clear. Thanks for the answer.