This tutorial will show you how to hide the last logged in Username in Windows by editing a security policy. But you’d have seen a similar article Hide Last Logged in Username in Windows, this article will describe how to do the same by editing the windows registry. This tutorial will be useful when applying this setting as a policy in a domain environment, but this can also be done on a normal workgroup environment using the secpol.msc command.
Go to Start -> Run or [Windows Key] + R and type secpol.msc, the “Local Security Policy” Window opens. Navigate to Local Policies -> Security Options and look for the policy “Interactive logon: Do not display last user name” and change it to enabled. To apply the changes immediately go to Run and type gpupdate.