No applicable update data was found

So I changed my hard drive in my fat ps3 (NOR system) and I was running rebug 4.82 but after plugging the USB into the PS3 in order to reinstall the CFW, the message 'no applicable update data was found'. I have the files/folders like this:

USB > PS3 > UPDATE > PS3UPDAT.PUP

all in caps, is there anyway I can fix this? Sorry if this isn't the right place, don't come here too often