I have just installed an evaluation copy of UV5. I opened an existing project (which previously compiled without errors. Now when I build I get the error "Cannot open Reg932.H" In the "Manage Project Items" window I tried de-selecting "Use Settings From TOOLS.ini" and set the "INC" option as "C:\Keil_v5\C51\INC" and got the same result. When I explicitly declare the include file as C:\Keil_v5\C51\inc\Plilips\REG932.h everything is fine. The only difference I can see between an example project (which uses the same processor and works fine) and my project is that my project is located on a different drive.