Enforcing an IE default page via GPO

You can set IE home page through Group Policy.
1. Create a GPO and link it to a scope (Site, Domain or OU level not group) that contains all your specified user accounts.
2. Edit the GPO: GPO name–>User Configuration–>Policies–>Administrative Templates–>Windows Components–>Internet Explorer–>Disable changing home page settings–>Enable–>Home Page: input your specified home page
3. Logoff or restart user computer to apply this GPO