Hi Ali, is your logon for Windows 7 an administrator account?

I'm not aware of any encrypted fonts either freeware, donationware, or commercial.

Which type of fonts are you installing? Type1, truetype, or open type?

Type1 fonts are a bit long in the tooth (getting old) so unless you have a specific need for a Type1 font skip them entirely.

If you are installing a truetype and an opentype font that have the same name, only one will show in your font list not both. Best to install only one type of font, not both.

If you use Xara3D any version, install truetype fonts because Xara3D doesn't "see" open type fonts.

If you are not using Xara3D then install an open type font if you have the choice between truetype and open type.