With the provided information I cannot be sure what is the exact problem and why it is occurred.
Currently I can assume that this is due to a known rendering issue when RadEditor control is used with an Ajax control and initially is hidden. If this is the case I would recommend following this forum thread
, in which possible solutions for this issue are provided.
If this does not help you, please get back to me with a simple, isolated project
, so that I could be able to investigate the problem on my end.
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