This afternoon is ready to write a UC / OS-II program to compile, according to the UC / OS-II author's prompt, copy the example file to the new MyProject folder and modify the base environment variable in the makefile, but compile Never passed. Weird, the author's example file I didn't change it at all, just changed a folder, how did it not? Later, I noticed that myProject had 9 letters and did not recognize correctly in the DOS virtual environment. I change myProject to Project, everything is OK!