Hello Jo Bert,
I am not able to reproduce and confirm such a behavior.
For test purposes I used the following online demo which saves RadEditor content in a database.
To answer your question: this is not the expected behavior. The editor should transfer to the server any content that is entered on the client - be it asterisks, underscores or other characters.
Furthermore, you are the first person to report such an issue. At this point it seems that the most likely reason would be in the code that you execute to save the editor content. Providing us with the exact error message would be of great help to provide more feedback.
the Telerik team
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