I didn't think it would work...as a lot of users are posting about it, not working. I wouldn't suggest this method to users anymore. If MS wants to put out an ISO free to download, they will. As it stands now and according to the blog and post's reports, the only way to update the OS from now on will be through MS store and through the new PC settings update....personally of which I don't like either of.
I would prefer an ISO to clean install with...since this is a new Alpha test OS, getting an ISO to clean install is highly unlikely for future builds. Now I imagine like windows 8/8.1 consumer preview ISO, 10 will have the same preview ISO....then the full release ISO for those that are fortunate to have access to one...eg MSDN subscribers and MVP's.
You are one of the fortunate few that it does work. for but the the ones it doesn't work for, far out numbers the ones it does work for. I've seen forum posts and blogs that it does work for, which is great. For the masses, it mostly a no go. I'm wondering if it's related to the hardware of those it's not working for. Who knows at this point....anything is possible.
I'm sure looking forward to 10 being released to the public...I really like way better then 8/8.1.
The ESD is merely an encrypted ISO. MS, god bless them, have chosen to only send it in that format, for update purposes. Only real reason I can think of, is a wrongly typed instruction, or a bad decrypt download. As we are all aware, the command line is unforgiving and a small typo can lead to a failure. This would result in a failure to write the ISO. During this process, the hardware is not involved in any way. No. I cant see how it can be hardware related.except !!, the update is sometimes assuming, in certain cases, that the hardware drivers are already on the system. Running the ISO from boot, of course, assumes nothing and only puts in the drivers it has in the package. But, going back to my first para, I do mean that I have never failed to produce the ISO. Installing on several different machines can, of course, have the usual hangups which we have all experienced before with previous OSs.