I have been doing an Windows 10 in-place upgrade using SCCM and manual installations from a file share. There are some PCs that complete the installation but after the last restart instead of booting Windows 10 they restore back to Windows 7. For others, users use them for some time then at some point in time they restart and revert back to Windows 7. I have not been able to know the reason why they behave this way and what I should do to correct this problem. What could be the reason and the possible remedy to this issue?