How to get free of old domain services in a notebook with Windows 8

Question

I have a Dell notebook that was connected to a domain in my work but now I’m out and don’t want any traces of my ex-work domain’s permissions, etc. The notebook is mine and I have administrator local privileges but, even so, I think that the notebook is somehow attached to some restrictions of the old domain. I already made several changes in order to get my notebook just personal and out of their net but still there’s some actions I cannot achieve to change. Yesterday, I finally got to uninstall the Trend Micro Officescan changing the regedit so that I could uninstall it without the password. I already renamed and changed the group to Worksgroup (Default) but I know there’s something still restricting the machine, not only blocking some installations, but interfering in my internet connection. I also think that my Windows update has some restrictions.
I don’t have any experience in domain servers or net servers or what else. I just wanted to have my computer free of any traces that are impeding me to have full access to my system. One of the things I want to do is to update my Windows 8 Pro to 8.1 so that I can install Windows 10 for free. I don’t even get to install Dell Assist because it cannot download Netframework 2.0 and 3.0... Yesterday, I could install Netframework 3.5 but still Dell Assist could not be installed. After uninstall Trend Micro Officescan I noted the the computer became slower. I don’t know if it’s related...
I apreciate any help that can guide me to resolve these issues.
Ane

Answer 1

Delete the entire registry key
HKLM\Software\Policies\Microsoft\Windows\WindowsUpdate
which will revert the WUAgent to the original installed behavior of Automatic Updates and then set the desired behavior using the Control Panel | Windows Update dialog.

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Answer 2

Also note windows 8 is not currently supported here on QnA. They're actively answering questions in dedicated forums here.
https://answers.microsoft.com/en-us/windows/forum/windows8_1

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Answer 3

"I just wanted to have my computer free of any traces"

The simplest solution is to clean install it from installation media.
https://www.microsoft.com/en-us/software-download/windows8ISO

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Answer 4

Ok, could you help me to setup Windows Update so that it can find the updates normally?

Answer 5

What happens when you try? Are you logging on as local administrator?

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