PieterCM

The only solution I found so far is adding a little CSS-hack under Appearance/Editor/Styles/Edit/Additional CSS:

footer {
margin-top:0px !important;
}

I found out that the solution is to change your web.config:

<handlers>
        <add name="php-8.3.11" path="*.php" verb="GET,HEAD,POST" modules="FastCgiModule" scriptProcessor="C:\Program Files\PHP\v8311\php-cgi.exe" resourceType="Either" requireAccess="Script" />
</handlers>

to

verb="GET,HEAD,POST,OPTIONS"

Apparently, WordPress uses the OPTIONS verb for its site_editor.php. IIS does not automatically add that verb to its web.config when enabling PHP usingt he PHP manager.

Apart from that, WP works fine on IIS (using PHP 8.3.11)

oh man, I found the issue

IIS PHP Manager added lots of handlers in web.config. I removed them all, except:

 <handlers>
      <clear/>
      <add name="php-8.3.11" path="*.php" verb="*" modules="FastCgiModule" scriptProcessor="C:\Program Files\PHP\v8311\php-cgi.exe" resourceType="Either" requireAccess="Script"/>
      <add name="StaticFile" path="*" verb="*" modules="StaticFileModule,DefaultDocumentModule,DirectoryListingModule" resourceType="Either" requireAccess="Read"/>
    </handlers>

That solved the issue.

I tested WP on my localhost with IIS 10. There the issue does not show. So it’s not an IIS issue. It must be related to network connectivity, a firewall, or AWS, where my server is located.

Many thanks James and Jamie. I appreciate your help!

Some more interesting facts.

https:/xxx/wp-admin/site-editor.php performs nearly 2000 api fetches

My IIS gives up on it after +/ 500… (probably for security reasons).

I have noticed something.

The script https:/xxx/wp-admin/site-editor.php performs a lot of api-fetches (a few dozens). In (my) IIS, these fetches stop after 6 or 7 and then give up on it. PHP on my IIS seems to be configured to block very fast consecutive api-fetches.

Many thanks. I keep on searching…

The issue also shows in PHP 8.1.29 and in FireFox

I get these PHP errors though:

[06-Sep-2024 06:54:15 UTC] PHP Warning: PHP Startup: Unable to load dynamic library ‘php_gd2.dll’ (tried: C:\Program Files\PHP\v8129\ext\php_gd2.dll (The specified module could not be found), C:\Program Files\PHP\v8129\ext\php_php_gd2.dll.dll (The specified module could not be found)) in Unknown on line 0
[06-Sep-2024 06:54:15 UTC] PHP Warning: PHP Startup: Unable to load dynamic library ‘php_xmlrpc.dll’ (tried: C:\Program Files\PHP\v8129\ext\php_xmlrpc.dll (The specified module could not be found), C:\Program Files\PHP\v8129\ext\php_php_xmlrpc.dll.dll (The specified module could not be found)) in Unknown on line 0

Does WP depend on php_gd2 and / or php_xmlrpc?

Forgot to mention: I’m on 6.6.1, and I reinstalled it several times, just to be sure…

Thank you for helping me out.

1. IIS is on PHP 8.3.10, I also tested PHP 7.4, same problem
2. MySQL is on 8.0.28
3. Using Chrome
4. I have zero plugins and only 1 theme (Twenty twenty four) installed.

I have meantime:

1. Changed the anonymous user from IUSR to an administrator account in IIS
2. Had a look at the logfiles. No 404 or 500, only 200 and 304 status codes
3. Disabled all output caching for that site in IIS
4. Changed the application pool to recycle every single request
5. None of that helps.

As for JavaScript errros, I get loads of warnings like these:
Third-party cookie will be blocked in future Chrome versions as part of Privacy Sandbox.

I do get 1 JavaScript error as well:
[Report Only] Refused to frame ‘https://ogs.google.com/’ because an ancestor violates the following Content Security Policy directive: “frame-ancestors ‘self'”.

And lots of these too:
[Violation] Added non-passive event listener to a scroll-blocking ‘mousewheel’ event. Consider marking event handler as ‘passive’ to make the page more responsive. See https://www.chromestatus.com/feature/5745543795965952

I have no idea if all that matters… Thanks again for your help.