Upgrading from D6 to D7

I have just successfully upgraded my D6 site to D7.

There is one outstanding problem, which is to do with CCK. I have run the Migrate Fields module, and successfully converted most of the fields in my custom CCK. However, there is an image field that remains stuck in the UNAVAILABLE FIELDS category with the following error message:

• Missing field module: 'image'. This field cannot be migrated.
• Changed field type: The 'field_logo' field type will be changed from 'filefield' to 'image'.
• Missing widget: The 'image' widget is not available for the field_logo field, it will be set to the default widget.
• Missing formatter: The 'image' formatter used in 8 view modes for the field_logo field is not available, these displays will be reset to the default formatter.

In addition to the above, when I try edit the custom content, there is no Image option under the Field Type dropdown. I think that this should be there as a default option?

So, it seems that someone the 'image' widget did not install correctly when I converted to D7.

Any suggestions on how to get around this?