To access /home you need rootsh installed. Without rootsh, Xterm automatically opens in /home/user/ and will not allow access below this level.

Regarding your original issue, it's as simple as this: Either you are not in the right folder or you are entering the file name wrong. Make sure you use Tab in Xterm to autocomplete filenames and directory names.

Btw, is there a reason you are not just using file manager to rename the file?