Probleme mit DCE nach Update von 7.6 auf 8.7

[Landsat]

Hallo zusammen,
ich habe eine Update von TYPO3 7.6 auf 8.7 durgeführt. Alles hat gut geklappt bis auf eine Sache.
DCE Inhalte werden nicht dargestellt.
Die Fehlermeldung lautet: ERROR: Content Element with uid "21" and type "dce_dceuid5" has no rendering definition!
Die Inhalte wie Texte und Bilder sind vorhanden wie auch die DCEs mit den Feldern und Vorlagen.
DCE Version 1.4.7
Wo könnte der Fehler sein?
Vielen Dank, Sepp

[takovbg]

I had the same problem.
Try uninstall DCE, clear the BE cache, and then again install DCE.
...

I passed through the next steps in clean Typo3 vers.8.7.10 installation (you don't need to passed through them - I just wrote to see how to riched the solution):
1. First installed the DCE 1.5.2
2. Created some DCE but there was a problem in FE
3. Deinstalled DCE 1.5.2 and installed older DCE vers.1.4.2 (the reason for using this version is that I used is successfully in T3 7.x before)
4. Showed the DCE from point 2 above in FE and it worked.

5. After this I created few other DCEs but they didn't work in FE - the same reason about which you wrote here.
6. Deinstalled 1.4.2, cleared the BE cache, then again installed 1.5.2
7. Opened page in FE and... it worked  :-)

8. Then decided to edit some DCE - added new field.
9. Opened the CE DCE in the BE but didn't see the new field.
10. Deinstalled the 1.5.2, cleared the BE cache, then again installed 1.5.2 (the same version)
11. Opened the page in FE and it... workes :

So I'm thinking in conclusion that the solution is - after you create a new DCE or edit one:
- deintall the DCE
- clear the BE cache
- re-install the same DCE again (or try with some other vers if this not work for you).

I'm in testing mode yet of the above solution but in some cases I'm seeing some working solution.

[takovbg]

Issue 2 (DCE 1.5.2 and T3 8.7.10) - "after creation of DCE element, and trying add it as CE in a page in BE then in the field "Type" you are seeing wrong identifier and neither any field which you created".

I deinstalled the DCE 1.5.2, cleared the BE cache, and again re-installed it (the same version). After then I added normally the DCE CE in the page and all fieds were shown for filling.
Also the FE showed normally.

[takovbg]

Confirm that deinstall, clear BE cache and re-install again solves the issue. T3 8.7.10, DCE 1.5.2.
Do this after create new DCE or after edit the structure of the DCE.

[takovbg]

There is a bug 2 - "DCE 1.5.2 (in Typo3 8.7.10) doesn't add template file - Template type: File". You have to use Inline template type - Template type: Inline.

[takovbg]

About the bug of non-using of template file (see the previous message above): 
Now I've decided to switch on the "displayErrors to 1 in Install Tool" as somebody suggested and see what would happen.
And, now the templating by file works! Strange, but works. It is not linked to the switching the displayErrors to 1 because then I switched off and the template file feature continues to work.


May be this is in result of deinstalling the DCE, cleared the BE cache and again installing the DCE as I did many times so far.
I have been doing this 3 actions after every new created DCE or editing the structure of some existing DCE because the changes can't apply without these 3 actions.
So for now this works in me (Typo3 8.7.10 and DCE 1.5.2.). But may be it continues to be an issue.

You could watch the process of the issue solving here: https://forge.typo3.org/issues/80350