If you use CuteEditor in Medium Trust environment, you need to setup temporary file location for AjaxUploader. Ajax Uploader is an easy to use, hi-performance File Upload Control which allows you to upload files to web server without refreshing the page.

Unlike standard ASP.NET HtmlInputFile control, AJAX Uploader does not read the entire uploaded file into memory. It streams the data into a temporary file while the data is received. For this reason, you must specify a temporary file location. You should ensure that the ASPNET user (NetworkService in Windows Server 2003) has read/write permission to this specified folder.

You can easily specify the temporary file location using the following method:

Setting temporary file location in web.config

Add the following code into the <appSettings> element of your application web.config file:

  <add key="CuteEditorTempPath" value="~/UploaderTemp"/>

In web farm environments, the Url that you specify must map to a central location, which is saved to by all servers in the farm. This can be done using a virtual directory that maps to a common shared folder on the network.

  <add key="CuteEditorTempPath" value="\\shareserver\temp"/>

---