sub-domain tries to access a non existing typo3 installation

Question

I have the following dir structure in my Server 2019 IIS. C:\inetpub\wwwroot\typo3 main Typo3 Web site C:\inetpub\wwwroot\typo3\Homepage second Typo3 Web site C:\inetpub\wwwroot\typo3\Homepage\ahnen webtrees web site

If I call the webtrees via https://www.myUrl.de/ahnen it works fine. But if I try to use the sub-domain https://ahnen.myUrl.de I got the following error message:

Warning: require(C:/inetpub/wwwroot/Homepage/ahnen/typo3/sysext/core/Configuration/DefaultConfiguration.php): failed to open stream: No such file or directory in C:\inetpub\wwwroot\typo3\sysext\core\Classes\Configuration\ConfigurationManager.php on line 92 Fatal error: require(): Failed opening required 'C:/inetpub/wwwroot/Homepage/ahnen/typo3/sysext/core/Configuration/DefaultConfiguration.php' (include_path='.;C:\php\pear') in C:\inetpub\wwwroot\typo3\sysext\core\Classes\Configuration\ConfigurationManager.php on line 92

The setup of the sub-domain pointed to the same folder than https://www.myUrl.de/ahnen, as you could see in the error message. But I have absolutely no idea, why the system is expecting a typo3 installation. What could be create this problem?

Answer 1

For an exact answer you provide to less information (and I might need more knowledge about IIS configuration)

I assume that https://www.myUrl.de points to an TYPO3 installation and that you want https://ahnen.myUrl.de to point to a subfolder of the webroot of that TYPO3 installation.

1. possibility: the 'subfolder' ahnen/ is no real subfolder but a page inside your TYPO3 installation
   then your ISS configuration points to a not existing folder in your filesystem. you have a fallback to nearest page and get a configuration conflict as your domain ahnen.myUrl.de is unknown to your TYPO3 installation.

2. possibility: there is a subfolder ahnen/ inside your primary webroot and there also is a TYPO3 installation, which might be misconfigured about the webroot of that subdomain, resulting in mismatched folders for resources.

3. possibility: your ISS configuration does not handle the subdomain correctly and starts the primary TYPO3 with not matching domain and folders, so TYPO3 becomes confused about locations of resources.