I wonder if you solved that situation with your Mac because I am facing the same situation.
I suspected RAM memory failure so I run MemTest86+ and Apple Diagnostics holding the "D" key when powering on the MacBook air, all with OK results.
Running Ubuntu 18.4 from USB and installing it is okay. All devices and options seem to work fine but the Factime Camera for which I believe there are not built in drivers for yet.
Nevertheless, the Mac will load the progress bar completely but stay in a loopback that can be seen with the verbose option (holding Command + V keys while powering on).
I tried creating different Maverick, Sierra and High Sierra USB boot disks from 8 to 32GB unsuccessfully and always with the same result: getting stuck once the progress bar has reached the end.
Still struggling with after three working days with no other option than using Ubuntu 18.4 so far without the camera but I need it for Skype, so too bad.
Thank you and with kind regards from Spain!
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=== Actualización (18/06/18) ===
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Hello,
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Finally I had to open the MacBook Air after reading some information about a sensor that could be failing and found some corrosion on the PCB, most likely caused by a small spill.
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After cleaning the board it's up and running again.
Hello Nav,
I wonder if you solved that situation with your Mac because I am facing the same situation.
I suspected RAM memory failure so I run MemTest86+ and Apple Diagnostics holding the "D" key when powering on the MacBook air, all with OK results.
Running Ubuntu 18.4 from USB and installing it is okay. All devices and options seem to work fine but the Factime Camera for which I believe there are not built in drivers for yet.
Nevertheless, the Mac will load the progress bar completely but stay in a loopback that can be seen with the verbose option (holding Command + V keys while powering on).
I tried creating different Maverick, Sierra and High Sierra USB boot disks from 8 to 32GB unsuccessfully and always with the same result: getting stuck once the progress bar has reached the end.
Still struggling with after three working days with no other option than using Ubuntu 18.4 so far without the camera but I need it for Skype, so too bad.
Thank you and with kind regards from Spain!