Hallo, aufgrund des Typo3 updates von 6 auf 7 muss ich auch die Ext DCE updaten.
Von  0.11.6  auf  1.2.5.

Bin nach folgender Anleitung vorgegangen:

Install latest DCE version (1.2+)
Go to install tool and do not perform "Database compare".
Because the first database compare in Install Tool renames the old DCE tables. 
This would be okay. But when you delete those tables after renaming them, 
before you've executed the upgrade scripts, the scripts are not able to do 
their job properly, because they try to migrate data from these tables. The 
wizard is also performing a database compare, so wait with a manual database 
compare until the migrations in the Upgrade Wizard are done.
Execute the displayed Upgrade Wizards in Install Tool:
Finally clear all caches. Done.

Bekomme im DCE Contentelement folgenden Fehler:
Data Structure ERROR: No ROOT element found for sheet "sDEF". Habe im Menü DCE auch: Update Backend Preview Template ausgewählt.
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