I have solved the issue temporarily by creating a index.html file that redirects to the index.php but I would prefer to have the server execute the php file directly.
What version of IIS are you on? Assuming it’s 7, do the following:
Open IIS Manager.
In the lefthand toolbar, expand the server node, then the Sites node beneath it.
Click on the name of your site.
In the main area of the window, under the IIS heading, you’ll see Default Document. Double-click it.
On the righthand side, under Actions, click Add.
Type “index.php” (without the quotes) into the popup and click OK.
That should do it. You might need to restart the site for this to take effect, not sure. If you do, just click the site’s name again on the lefthand dropdown, then on the right (under Manage Web Site), click Restart.
Thank you, I found it! But it is strange, because index.php is already there, although not at the top of the list. I will move it to the top and try again.