An hour ago I installed the last version of this software, then I opened my project and added some files with extension "*.h" I opened them as "C Files", then when trying to close them one of them closed, but I cannot close the others (I opened three of them). I already re-started my computer but I just can't get these files off my project. I right click the mouse over the file select "remove filename.h" and asks If I am sure I want to remove it when I select yes, it does nothing!.
I thought the .h files are added when uVision scans for .h file dependencies found in your .c files. If you are including those .h files in one or more of the .c files in your project then you can't and shouldn't be able to remove them from the project. - Mark
Yes, that's generally true & normal practice, but there's no law that says you can't compile a file called 'fred.h' to 'fred.obj' In fact, the Triscend FastChip99 software generates a .h file which requires you to do this! You might also want to add a .h file to the Project just so that it's there in the Project window for quick access. In that case, you'd clear the 'Include in Build' and 'Always Build' options (or have a Group with those settings).