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Entry type: FAQ Entry ID: 109803865, Entry date: 11/25/2021

How do you react when you try to open your PCS 7 and get the warning message "Open project (257:90) - The project contains errors in the internal data structure."?

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This waring message may appear several times when you open your project.


The reason for this warning are temporary files, that are not deleted due to so-called "unexpected events". 

One possible cause is that the project data is damaged by a crash or voltage drop.


Proceed as follows to fix the problem:

  1. Create a copy of your project using the menu command "File" and "Save as" with the option "With reorganization (slow)".

    The error is now fixed and the warning no longer appears when you open the project.

If the warning also appears with the project copy which was newly created by "Save with reorganization", delete the existing temporary files in the AS directory manually. Carry out the following steps one after the other:

  1. Warning: Back up (archive) your project first to ensure that no important information is lost and if necessary you can restore your project.
  2. Boot the central ES. Make sure that the project is not accessed after booting - neither by opening the SIMATIC Manager on the central ES nor by accessing from a remote ES.
  3. Search exclusively in the AS directories of your project for files whose name starts with "00", in other words, files with the following format: "00*.log". Files with extension "*.log" whose name does not start with a "00" must not be deleted, as this will affect the functionality of your project.
  4. Only delete any files found in the AS directories whose name begins with "00" ("00*.log"). Warning: make sure that you only delete files in the AS directories and not in the OS project directories.

The error is now fixed and the warning no longer appears when you open the project.

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