Moving WordPress Site – Permalinks Issue Perhaps?

Hi all,

Thank you in advance for considering my question.

My company up until yesterday had employed a WordPress developer who did not work out. He was hosting our half finished WordPress site on his own development server. We asked that he turn over all the files to us, which he did as a .zip containing the .sql file as well.

I am not a WordPress developer but I am a reasonably quick learner (or so I like to think) so I imported his .sql file to my database, swapped things out in wp-config, and decided to have a go at it.

It must still be linked to his own dev server – when I put in the new address http://katiemacdougall.ca/kore I can get a 404 but any links returns me to our old developers server where he has suspended our account.

ETA: Also I cannot access /wp-admin/ at all.

How do I go about fixing this?

Thank you in advance for your help!