When I trying to make a restore point manually, in the bottom of the window says: "System Restore disable by Group Policy" How can I fix this? I'll appreciate if someone help me to fix this.
Is the machine a domain member? (Is it a work PC?)
The problem certainly sounds to be policy-related, as if you've accidentally (or knowingly) applied policy on your own machine, or the domain admin has set a domain policy preventing system restore.