1. Open Network and Sharing Center

   Right-click on the network icon in the system tray and select "Open Network & Internet settings."

   Click on "Network and Sharing Center."

2. Change Adapter Settings

   In the Network and Sharing Center, click on "Change adapter settings" on the left sidebar.

3. Select the Network Adapter

   - Right-click on the network adapter you are using (e.g., Ethernet or Wi-Fi) and select "Properties."

4. Internet Protocol Version 4 (TCP/IPv4)

   In the Properties window, find and select "Internet Protocol Version 4 (TCP/IPv4)" and then click "Properties."

5. Update DNS Server Addresses

   Select "Use the following DNS server addresses."

   Enter the preferred DNS server and alternate DNS server addresses.

   Click "OK" to apply the changes.

6. Flush DNS Cache

   Open Command Prompt as an administrator.

   Type `ipconfig /flushdns` and press Enter to clear the DNS cache.

If you're managing a DNS server (e.g., Windows Server with the DNS role installed), follow these steps:

1. Open DNS Manager

   On the server, open the "Server Manager."

   Click on "Tools" and then select "DNS" to open the DNS Manager.

2. Select the DNS Server

   In the DNS Manager console, expand the server name to see the DNS zones.

3. Choose the Appropriate Zone

   Expand "Forward Lookup Zones" or "Reverse Lookup Zones" to locate the zone where you want to update records.

4. Add or Update Records

Good Rule of Thumb: you can delete the internal records that point at the old site and create new records that match the External records – or you can update the existing records to match the External records following the same format. 

   Right-click on the zone and select "New Host (A or AAAA)" to add a new record.

     Enter the name and IP address for the new host.

     Click "Add Host."

   To update an existing record, locate the record in the list, right-click it, and select "Properties."

     Modify the necessary details and click "OK."

5. Apply and Save Changes

   Make sure to apply any changes and save the updated records.

6. Clear DNS Cache on Client Machines

   Ensure client machines clear their DNS cache to use the updated records:

     Open Command Prompt as an administrator.

     Type `ipconfig /flushdns` and press Enter.

After making changes to DNS records, you can verify the updates:

1. Use nslookup

   Open Command Prompt.

   Type `nslookup <hostname>` and press Enter to verify the DNS record for the specified hostname.

2. Ping the Host

   Type `ping <hostname>` to check if the hostname resolves to the correct IP address.

• DNS Cache

If changes are not reflected immediately, ensure that the DNS cache on both the server and client machines is cleared.

• Replication

 In an Active Directory environment, ensure that DNS changes are replicated across all DNS servers.

• Network Issues

Verify that there are no network connectivity issues preventing access to the DNS server.

• Local Hosts

Windows has a local "hosts" file to override DNS or provide resolution for servers that aren't in DNS. This can cause confusion.

This can be found in %WinDir%\System32\Drivers\Etc\hosts (Usually C:\windows\System32\Drivers\Etc\hosts)

Link to Microsoft help article on restoring local hosts to defaults

By following these steps, you can effectively update internal DNS records on a Windows PC or server. If you have specific questions or encounter issues, feel free to ask your IM.