Anyone else having this issue? I have the latest 10.12.5 mac OS along with the macosupd10.2.5 patch but no go.
Solved
Cant create a boot usb or netboot to image on iMac (Retina 5K, 27-inch, 2017) Model Identifier: iMac18,3
+11Best answer by mcarver
You have a forked macOS issue. Best option is to wait until 10.12.6 is released and build off it. These are 2 sites that are good to have bookmarked: https://support.apple.com/en-us/HT201260 and https://support.apple.com/en-us/HT204319. They should you the OS and build that is shipped with each model and what builds the App store releases.
+18I'm pretty sure that model has it's own forked version of 10.12 so the dmg would need to be captured directly from it.
+17Even if that is not the case, I can't create working 10.12.4 or 10.12.6 NetInstall due to getting signing errors on install which is a known issue with Apple.
+17Even if that is not the case, I can't create working 10.12.4 or 10.12.5 NetInstall due to getting signing errors on install which is a known issue with Apple.
+15We are as well - although we haven't tried with the new iMacs yet - we are having a lot of difficulty imaging with a Netboot image running macOS 10.12.5.
Rather than block copying our OS DMG file, it unmounts the drive, says its block copying and then a few seconds later says it's finishing block copying.
+7You have a forked macOS issue. Best option is to wait until 10.12.6 is released and build off it. These are 2 sites that are good to have bookmarked: https://support.apple.com/en-us/HT201260 and https://support.apple.com/en-us/HT204319. They should you the OS and build that is shipped with each model and what builds the App store releases.
+5literally just finished building the forked image and NBI as above yesterday (thanks to everyone on forums!:) now today 10.12.6 dropped.. any verification that this gets rid of the need to create forked boot NBI and image?
+15@techmchs I'm building a base OS with the 10.12.6 installer now to test with Netboot. I'll report once it's done and I've tried imaging.
+15While this may work for folks, I'm still experiencing the issue I mentioned in my previous post where the OS DMG file is not block copied.
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