Hi Ali Faraji,
What do you mean by fails to upload. Is the uploaded files collection empty? As far as I understood you try to upload a compiled dll, right? And it fails to insert If you change a line of code and then recompile the dll? I am afraid that we can hardly reproduce such problem in our local environment. Could you please open a support ticket, attach the failing dll as well as the aspx page that uploads it so that we can take a look. A troubleshooting step that you can take in the mean time is to try to upload the same file using a regular ASP.NET FileInput and observe whether the issue persist.
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