When, for example, the settings such as substituting the NTT JTeX Japanese font by a Windows font (Q_O3) are made on the [JFont2] property sheet and saved by [Save], there is the -vfn: setting on this sheet. If this is not blank, register it on the Registry.
-vfn: above can select either reading an external file containing the Japanese font settings or Japanese TrueType settings by [WinJFont] (this also corresponds to -vfn:).
If errors are set in -vfn: in the Registry, the Japanese font settings become invalid.
The original state is recovered by setting empty in -vfn: in [JFont2] and [Save]ing it. Moreover [Default] button in [WinJFont] makes the setting there in the default state, which is again saved by [Save].