2.3 admin previous entries links broken

I manage a few sites using WordPress on an IIS server (I know, not ideal, but it’s out of my hands and there’s no way around it) and have just noticed that the newer ones I have built using WordPress 2.3 have broken ‘Previous Entries’ links in the Admin Manage Posts page.

In 2.3, the links appear as:
http://www.domain.com/wp-admin/?paged=2
which when clicked goes back to the Dashboard page rather than showing the previous entries.

Back in one of my other sites using 2.2.1, the links appear as:
http://www.domain.com/wp-admin/edit.php?paged=2
and correctly show the previous posts.

I’m in the middle of building a large site with a number of posts and really do need to go back and edit some of these previous posts urgently.

Could someone please provide me with some instructions on how to either:

1. Edit the edit.php file (or whatever file has been changed) so that the links point to the correct location.

or

2. Advise me on the best way to rollback a fresh 2.3 installation to a 2.2.1 installation (because I know that one works).

Thanks in advance!