The generator creates the CLW file.
If the generator fails to update the CLW file, then you'd see this issue.
The compiler compiles the CLW file into an OBJ.
If the compiler fails to compile the CLW then you'd see this issue.
The linker links the OBJ's into a DLL or EXE. If the linker fails to find the new OBJ, and uses an old one instead, then you'll see this issue.
Also - The Build Menu in the IDE has a "Clean solution" option, which removes OBJ's to force the compiler to remake them.