Hi Amir,

I have just seen it the same issue, just with templates instead of document types.

http://our.umbraco.org/forum/templating/templates-and-document-types/53232-Cant-save-or-delete-template

Did you try check the log file in /app_data/logs as suggested in the error message, to see if you can get some more useful info.

This error often comes if you have duplicate document types with the same name You could try reload the tree to see if there are two document types with the same name.

Hope this helps,

/Dennis

Delete all Generic properties and linked Templates, after that it works.

THIS

Delete all Generic properties and linked Templates, after that it works.

@Reto Rechsteiner Thanks, this did the trick.

I had the same issue with a document type, thought I'd deleted every property to try fix the problem, turns out I'd forgotten to delete a tab I'd created on this doc type that was stopping it from being deleted.

I don't see this as an issue at issues.umbraco.org, should it be? Deleting all properties before deleting a document type does work, but it's not intuitive and not hinted at in the error messages returned.

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