Error message trying to download libreElec to sd card

Hi, hope someone can advise. Trying to download to sd card but when pressing 'write' button the error message " error:couldn't open f:/libreelec-rpi2.arm-8.0.2.img.gz ". I've tried lots of times - checked its not- read only / formatted sd card and used another different brand new sd card , but still get same message. Would appreciate any guidance. Thanks