TYPO3 Exception 1166546734¶
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#1166546734 TYPO3CMSCorePackageExceptionUnknownPackageException¶
Reason 1:¶
- Package does really not exist
Reason 2:¶

- CamelCaseConversion Problem with numbers
- f.e. vendor_extension_2018 will be converted into VendorExtension2018 and converted back into vendor_extension2018
This will result in the following error message:
Package “vendor_extension2018” is not available. Please check if the package exists and that the package key is correct (package keys are case sensitive)
According to the hints in TER these kind of keys are invalid:
Reason 3:¶
1/1) #1166546734 TYPO3CMSCorePackageExceptionUnknownPackageException Package “” is not available. Please check if the package exists and that the package key is correct (package keys are case sensitive).
Happened on switching from LTS 9 to 10 as $_EXTKEY
is no longer defined. Therefore I called:
\TYPO3\CMS\Extbase\Utility\ExtensionUtility::registerPlugin(
'VENDOR.' . $extensionKey,
'Pi1',
'LLL:EXT:...'
);
With an empty $extensionKey