I have Acer V3-772G 1 TB Harddisk. I shrinked my biggest partition in order to install Kali Linux. When installing Kali, GRUB couldn't detect windows 8 so I kept going on(I installed grub as my masterboot). After installed Kali there was no way to boot Windows 8.1, but booting Kali was OK with GRUB in legacy-BIOS. When I tried to change bios to UEFI it couldn't find any OS (took too much time, nearly 1 hour). So I tried to update GRUB with boot-repair within a Ubuntu Live USB. But after updating GRUB I terrified, in UEFI and Legacy mode grub couldn't find ANY OS (Both Kali and Windows) so I have no option other than using Ubuntu Live. I tried every possible options but nothing has worked for me. I tried rEFInd in UEFI mode it worked only for Kali. I still cannot boot my windows 8.1 . I considered to restore to factory setting with a Windows Rescue USB but kept telling me "No driver found". Please help me to dual boot or remove Kali and restore my Windows 8.1