How I can solve this error, CC780KR error F0004 : illegal file name "main.c"?

Hello

I'm using R5F100G MCU and CubeSuite++ V2.02.00.

And I want to solve my problem.

The problem is that when I build my project, the error occurs to every file.

The occurred error is "CC780KR error F0004 file name "main.c".

I searched about this error, and the company notes this error is about 'There is an error in the format, characters, or length of the specified file name'.

However the file name looks normal. The names of my files are "main.c", "System_Init.c". So I don't know why error occurs and how to solve that problem.

Please tell me solution.

Thanks