I have here a rather new computer with a 250 GB SSD as start medium. The dealer has installed a current Windows 10 Professional 64 Bit system there on my request. At my request, the dealer configured everything in GPT/UEFI mode so that I could then install Linux in the free, i.e. not yet partitioned part of the SSD.
I created a bootable Antergos Live Stick with Rufus from Windows and - after some problems and good advice here in the forum - was able to install my Antergos as a new partition (sda5) in the unpartitioned area of the SSD. During the installation, however, the boot partition (sda2), which apparently controls the boot conditions of the operating systems, also had to be changed. Of course, I made sure that this existing sda2 was not formatted. Result:
Antergos now runs fine, but the Windows system is no longer recognized. So I can’t run Windows anymore. Maybe I have to set up my quite new computer completely new, first Windows 10, then a special boot manager, then Antergos? But maybe there is also a solution to make Windows run again without a complete rebuild?
Translated with www.DeepL.com/Translator