Computers have provisions for adding accounts for multiple users, so that more than one person can log in without interfering with others' access. Typically, each system would have 2 accounts: administrator and guest.
Some users comment that when they try to add a user account in Windows 10 they see it The Add someone else to this PC link is greyed out.
Since the option itself isn't available, we can't add any more accounts. Obviously, we need to verify that you are logged into the system as an administrator, but there could be more reasons. Try the following troubleshooting solutions one at a time to fix the problem:
Solution 1] using NETPLWIZ
1] Press Win + R to open the Run window. Write the netplwiz command to open the User Accounts window.
2] Click the Add button to add the account. However, this method would require mention of the domain. Consult your network administrator for the same.
Note: The options differ for users who want to log in via their Microsoft account and for those who want to log in via their local account, the former being the simplest.
Solution 2] Temporarily disconnect the Internet
Try adding a user account while you are disconnected from the internet. Disconnect the network cable or disconnect the Wi-Fi or disable the LAN and try again.
Solution 2] Enable the integrated administrator account
1. close cmd in the Windows 10 search box.
2. Right-click the CMD icon e run as administrator.
3. Now, copy the command given below and paste it into the Command Prompt window and hit the Enter key to run it.
net user administrator /active: yes
Now close the Command Prompt window and try again.
Solution 5] Update Windows
Windows Update updates everything from associated drivers to security options. Therefore, many of the possible causes behind this problem could be solved with a simple Windows update. Here is the procedure file to update Windows.
I hope this helps!