I had a dual boot installation with Windows 10 and Ubuntu 16.04. One day I got a screen No boot device found and I couldn't enter neither of the OS installed on my laptop. So after reading ways to solve this problem, I decided to switch the UEFI mode to Legacy mode. This way I was able to access the Windows OS only.
However, then I changed back again to the UEFI mode, but unfortunately there was no ubuntu option anymore, and the disk partitions dedicated to Ubuntu were not visible anymore in Windows OS file manager, although I could see the partitions inside the Windows 10 disk configurator app.
Any advice how can I restore the ubuntu as an UEFI option if possible? Or save the partition at least?