The issue may be coming from a number of different sources therefore I will need some more information in order to narrow down the causes:
- do you have custom navigation used in your project or you are using the default control? Generally we have observed similar behavior in one particular case, when the client had used a template that got a mixed reference and was referencing itself - this has caused the same OutOfMemory exception on the frontend and unresponsive backend when editing the page based on this template.
- can you provide us with the full stack trace of the error.
Also the following thread might help you:
All the best,
the Telerik team
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