Hello Davide,
The process will involve introducing another Windows Server, then promoting that server to a domain controller. After it has successfully synchronized, you can demote the old server. During this process, you'll be migrating the functional levels of your domain and forest as well.
Here are the steps in detail:
1. **Prepare a new Windows Server**:
Prepare a new Windows Server 2016 or 2019 as a virtual machine to act as your new Domain controller.
2. **Add Role**:
On the new server, go to Server Manager > Add Roles and Features > Active Directory Domain Services > Install.
3. **Promote Server to Domain Controller**:
Once the role is installed, click on the notification icon and select "Promote this server to a domain controller". Choose "Add a domain controller to an existing domain", enter your domain name and credentials.
4. **DNS and GC Configuration**:
Make sure the boxes for "DNS Server" and "Global Catalog (GC)" are checked. Do not check the box "Read only domain controller (RODC)".
5. **Replication**:
Choose the appropriate replication options.
6. **Setting a DSRM password**:
The Directory Services Restore Mode password is for restoring your domain controller in case of failure, set a password and remember it well.
7. **Prerequisites Check**:
At the end of the process, the server will run a prerequisites check. Review any warnings or errors. After it's done, the server will automatically reboot.
8. **Replication**:
Wait for the replication to finish. You can check the state of the replication by running "repadmin /showrepl" in the command prompt.
9. **Transferring FSMO Roles**:
Transfer the FSMO (Flexible Single Master Operations) roles from the old server to your new server.
10. **Update DNS**:
Update the DNS settings of your network so that your new DC is the primary DNS server.
11. **Demote the old server**:
On the old server go to Server Manager > Remove Roles and Features > Active Directory Domain Services > Uninstall. This will demote your old server.
12. **Upgrade Functional Levels**:
Now you can finally upgrade your domain and forest functional levels to match your new server's version.
Remember to backup all your data before starting the process. I would recommend hiring a professional if you're not comfortable performing these actions yourself.
Let me know if you need any more help.
Best regards,
AI Assistant.
