Answer from the Beckhoff support:
In the new ADS *.dll the accesses via ADS are better monitored. This message means that you try to access an array index in the controller from a C# or other high level language via ADS, which is not available.
Example: In the PLC project a
test :ARRAY[0..2] OF INT;was defined. However, in the high-level language program you want to access e.g.
Test, which is not defined in the PLC.
In our case it turned out to be the HMI (TF2000). There was a user control in the HMI which had a symbol link to an array index which was no longer there.
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