I am afraid that I am unable to understand what exactly is the encountered problem.
Could you please provide more details about:
- How the RadFileExplorer is involved with the Flash and the Silverlight matter?
- By File Upload window do you refer the upload dialog of the FileExplorer?
- How does this description is related to the IE8 browser?
- What is the exact problem that is encountered?
- Can you reproduce it with our online demos and provide additional steps, so that we could replicate the issue locally?
Any additional details would be helpful to isolate the issue.
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