Hosting company upgraded MySQL to 5.1 and the Portfolio plugin broke with database errors, saying that tables don't exist. I checked for solutions here and tried de-activating and re-activating. It hasn't solved the problem, and not mentioned in that post is that it deletes websites already entered by re-creating the tables. Argh!
I've got a database backup thankfully so I will be able to restore that table.
What I don't understand however is why the rest of my site is working indicating to me anyway that it's not an issue with table corruption.