When a user tries to reset their password on my site they

Hi,

When a user tries to reset their password on my site they are getting the error message 'Sorry, that key does not appear to be valid.'

I've checked the database and the key is different to the one that is emailed.
Is this is a problem with the plugin or Wordpress?
I've just updated the plugin as well but still have the same problem.

Also Google crawler is all of a sudden coming up with errors for wp-login.php?action=register not sure if this is a problem or not?

Thanks