Include path not found

I have moved my project resources--c files and h files--around a lot and so have had to change my include paths frequently. I am now getting all kinds of "Invalid Project Path: Include path not found: ..." type warnings that talk about directories I have deleted or moved. When I go into Properties and Include Paths, I cannot delete or remove the old paths and I'm not sure what file they're stored in. My project still compiles and runs fine as long as I add the valid new include paths. Any clues to remove these old paths and the warnings?

Thanks,

-Brad