Error 300 Muliple choices and now cant login or see wordpress

Hi All,

I think/know I have done something stupid but just not sure what to do about it.

I have 2 domains, co.uk and .com both have the same website (non wordpress) pointing at them. I created my wordpress installation on the root but under the folder wordpress.

I decide to try and test it only on the .com address, so set up a root direction eg mydomain.com/wp and then in the admin panel changed the settings to this address. However this didnt work so I then went on to move my wordpress folder to this root folder, so it became mydomain.com/wp/wordpress [wp being the root folder for that domain]

However I get an error 300 multiple choices The document name you requested (/index.php) could not be found on this server. However, we found documents with names similar to the one you requested.

How can I recover from this.

As a newbie and not so technical, please be gentle!