A mistake found in the will – can it be fixed or rectified?

Sometimes it is not until after a will-maker dies, when their executor is applying for a grant of probate, or seeking to administer the estate, that some kind of administrative mistake is discovered in the will.  For example words used in the will, or some mis-description, operate to prevent the will-maker’s intentions from being put into effect.  Resolving the problem usually requires making an application to the Court.  This causes expense and delay.

It is unfortunate that such genuine clerical mistakes or ambiguities are not picked up during will-making. Can anything be done when they are discovered after death?  Can they be fixed so as to preserve what the deceased intended to happen?  Or will it result in an intestacy?