Hi,
Do you have a folder website/UploaderTemp , and does it has permission to write file?
Please try this way , maybe you can get error details:
<CuteWebUI:Uploader ID="ctlFormUpload"
OnFileUploaded="ctlFormUpload_FileUploaded" runat="server"
FileTypeNotSupportMsg="Please upload only .doc or .docx files"
UploadType="IFrame"
>
Regards,
Terry