I have a Lenovo G50-70 and ever since an Windows 10 update it won't boot. I've tried booting through Windows media recovery tool USB to make a Windows 10 clean install but it says I have 0 space for partitions, so I can't complete the process. I've also tried changing from UEFI mode to legacy (it just restarts nonstop) and changing BIOS settings to default and factory settings in the BIOS menu. Still the same thing happens. The error window says "Default boot device Missing or boot failed." However the hard disk appears on the informations tab of the BIOS menu. What eles can I try?