MSIX error screenshot

This turn out to be because the VHDX drive I had created on my work laptop, despite being created as an admin, was instantly getting set to write protect for data security reasons.

It would be VERY useful for Microsoft to say “We can’t write to the drive due to it being set to read-only” instead of the meaningless error it spits out.

Also, if running in powershell, make sure the powershell window is running as admin.