TYPO3 Version 6: Fix Login Error

Description of Problem

With some installations of TYPO3 Version 6, it may occur that access to the Backend is no longer possible. Either the login process causes error 500 or the process seems to hang up. 

Cause

The reason for this is the outdated TYPO3 extension rsaauth, which has not been supported in IONOS web hosting since the end of July 2020. TYPO3 installations that still use rsaauth for authentication can therefore no longer access the Backend.

Rsaauth was originally introduced to protect passwords by encrypting them during transmission. However, compared to HTTPS, rsaauth has more disadvantages than advantages, which is why rsaauth is officially considered obsolete and should no longer be used. 

Solution

To get access to your TYPO3 Backend again, deactivate rsaauth in your TYPO3 configuration:

• Download the files LocalConfiguration.php and PackageStates.php from the /typo3conf directory of your TYPO3 installation to your computer.
  
  Transfer Files Securely with FTP

• Edit the LocalConfiguration.php file with a text editor and replace each line that says 'loginSecurityLevel' => 'rsa' with 'loginSecurityLevel' => 'normal'.

• Open the file PackageStates.php with the text editor and go to the following section:

  'rsaauth' =>
    array (
      'manifestPath' => '',
      'composerName' => 'typo3/cms-rsaauth',
      'state' => 'active',
      'packagePath' => 'typo3/sysext/rsaauth/',
      'classesPath' => 'Classes/',
       'suggestions' =>
      array (
         ),
      ),

• Change the line 'state' => 'active', to 'state' => 'inactive'. The section will now look like this

  'rsaauth' =>
    array (
      'manifestPath' => '',
      'composerName' => 'typo3/cms-rsaauth',
      'state' => 'inactive',
      'packagePath' => 'typo3/sysext/rsaauth/',
      'classesPath' => 'Classes/',
       'suggestions' =>
  array (
         ),
      ),

• Upload the updated files back into the /typo3conf directory.

You can now log back into the TYPO3 backend.