TYPO3 Exception 1389265900¶
Below, the TYPO3 community may have provided additional information or solutions for this exception. However, these may or may not apply to your particular case. If you can provide more information, you should come back here and add your experience and solution steps to this issue once you have resolved it.
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You are not allowed to access the backend as your IP does not matches the [BE][IPmaskList] setting in the Install Tool.¶
Go to the Install Tool and add your IP address in All Configuration
['BE']['IPmaskList'], using comma separation (no semicolon).
See also https://docs.typo3.org/typo3cms/SecurityGuide/GuidelinesIntegrators/GlobalTYPO3Options/Index.html#ipmasklist for more security advice.