This definitely falls in the category of "You should know better."
I lost the domain controller on my home network a while back. I've been running my other computers (a desktop and laptop) without a DC since then, and it let's me login from the cached passwords. But this morning I brought the newly build domain controller online, and this evening I fired up my laptop. Well, of course, the new Active Directory service knows nothing about my old logins, and the laptop won't let me on.
So I go to the DC, and create the same user with the same password as before, but, I know, the security identifier's different, so the machine thinks it's a different users. After logging in to the local admin account on the laptop and joining the machine to the domain, I login as my regular domain user, and it creates me a new profile.
Well, of course, now I don't have access to any of my old files, and my local data is in the old profile.
So I logged in as local admin again, and granted permissions and ownership on my old C:/Users/dave directory to the new DOMAIN\dave user. And then, hoping to get my old profile back, I went into regedit and did a search for everywhere that it was pointing to the new profile directory (C:\Users\dave.DOMAIN) and changed it to point to the old one (C:\Users\dave). And then tried to login in.
I get "Group Policy Client service failed the login"/Access is denied.
I googled it, and found something about wiping out the profile by changing the Guid in the HKLM/Software/Microsoft/Windows NT/CurrentVersion/ProfileList, in hopes that it would create a new profile, but I think that may have made matters worse.
I still have admin access to the machine, so my data is not at risk, but short of backing up my data, reinstalling windows, and then copying the data back that I need, I can't seem to get on as me.
Any suggestions?
Thanks for rescuing me from my own foolishness.
Best Answer
So first off, this is usually why you have two DCs in the environment, as Bad Things happen when you lose the DC and don't have a backup.
This on the surface seems like an easy thing to fix if you still have admin access to the files. Personally, I'd just stick with a new user account, and then move over all your files from the old profile into the new one.
Generally speaking, mucking about in the registry can only lead to more Bad Things as well. Usually...