  I present pointed ROSAT PSPC observations of the pre-cataclysmic binary V471
Tauri. The hard X-ray emission (>0.4keV) is not eclipsed by the K star,
demonstrating conclusively that this component cannot be emitted by the white
dwarf. Instead I show that its spectrum and luminosity are consistent with
coronal emission from the tidally spun-up K star. The star is more active than
other K stars in the Hyades, but equally active as K stars in the Pleiades with
the same rotation periods, demonstrating that rotation--and not age--is the key
parameter in determining the level of stellar activity.
  The soft X-ray emission (<0.4keV) is emitted predominately by the white dwarf
and is modulated on its spin period. I find that the pulse-profile is stable on
timescales of hours and years, supporting the idea that it is caused by opacity
of accreted material. The profile itself shows that the magnetic field
configuration of the white dwarf is dipolar and that the magnetic axis passes
through the centre of the star.
  There is an absorption feature in the lightcurve of the white dwarf, which
occurs at a time when our line-of-sight passes within a stellar radius of the K
star. The column density and duration of this feature imply a volume and mass
for the absorber which are similiar to those of coronal mass ejections of the
Sun.
