TYPO3 Exception 1478105826


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FlexForm location was not found, TYPO3 12.0

Data structure file "EXT:my_extension/Configuration/FlexForms/NotExisting.xml" could not be resolved to an existing file

When opening a plugin in the backend and the referenced FlexForm is missing.


Correct the path to the flexform in method ExtensionManagementUtility::addPiFlexFormValue(), which is usually called in EXT:my_extension/Configuration/TCA/Overrides/tt_content.php.

Using $_EXTKEY in configuration files in TYPO3 v9 and above

This error can happen when using the variable $_EXTKEY in a TCA definition like Configuration/TCA/Overrides/tt_content.php without defining it. In TYPO3 versions before 8 the variable was automatically defined.


Replace all occurences of $_EXTKEY with the extension's name or define the variable locally.