Where is slider photo files? which name?

Thanks for your great simple catch template. I just want to put photos on theme slider but when I tried to put the photos, it doesnt work. the word Press ask me to log in even i am already log in.... I don't know maybe it is problem of cach or another theme which I download before? anyway, Please give the name of files and which directions for these photo where it goes up loaded for main page theme slider? Thanks again. konaka-residence.com