Basically you would follow this procedure found in the link below. All I had to do was download the XPEnoboot, made a bootable usb drive, insert into the last USB port in the back of the unit, download and install synology assistant, have a new drive in the EX495, turn on the unit and wait 10 to 20 seconds and use synology assistant to scan over the network. Once it's scanned, it'll download the firmware and install it into the unit.
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