Hello,

The Reset Firefox feature can fix many issues by restoring Firefox to its factory default state while saving your essential information.
Note: This will cause you to lose any Extensions, Open websites, and some Preferences.

To Reset Firefox do the following:

1. Go to Firefox > Help > Troubleshooting Information.
2. Click the "Reset Firefox" button.
3. Firefox will close and reset. After Firefox is done, it will show a window with the information that is imported. Click Finish.
4. Firefox will open with all factory defaults applied.

Further information can be found in the Refresh Firefox - reset add-ons and settings article.

Did this fix your problems? Please report back to us!

Thank you.

Hola, no, no lo solucionó.

Justo después de hacer la pregunta, encontré un programa en internet que modificaba el registro. Este programa lo ejecuté en "modo a prueba de errores" y así se arregló el problema.

Resetear firefox no funcionó yo lo había ejecutado previamente.

Te agradesco tu respuesta.

Saludos.