[TYPO3-english] Error message after change core to v7

[Matrix85]

hi,

after i change the core symlink to the typo3_src-7.6.9 i became this error message at / typo3/ or /typo3/install:

Fatal error: Class 't3lib_error_ErrorHandler' not found in /yyy/test_v7/typo3_src-7.6.9/typo3/sysext/core/Classes/Utility/GeneralUtility.php on line 4536


i remove all files in the typo3_temp directory - but it didnt help.

have somebody a idea, what i can do? the server run with php 5x5, so i think this isn' t the problem, too.