Hello!
This is an odd problem I've stumbled into and hoping I might find some help here.
I've customized the latest server 2019 ISO using this method:
1) Apply install.wim to new VM
2) Boot VM to audit mode
3) Apply new packages, patches, etc
4) sysprep /generalize /oobe
5) DISM capture new install.wim from VM
6) Rebuild ISO with new install.wim
The resulting ISO works perfectly for fresh installs as well as normal upgrades. HOWEVER, when upgrading a machine where the built-in 'Administrator' account has been renamed, the upgrade results in the machine having TWO accounts with the same xxxxx-500 SID: the original, renamed account and a second account named 'Administrator'. As you might imagine this is a major issue. It causes some strange failures (ex. opening local users in computer management crashes the whole machine). There's also no easy way to fix it that I know of, as removing a built-in account is not permitted. Maybe an offline tool but haven't tried yet.
following the same process with the server 2016 ISO yields the exact same result. The same process with the server 2012R2 ISO does NOT suffer from this issue.
Any thoughts or suggestions?
Thanks!