We had a requirement to add Copy/Paste icons the RadFileExplorer toolbar. That was the easy part. Getting them to call into the native Copy/Paste functions that are used by the Context Menus proved to be challenge.

Support provided me the solution below but it would have been nice to have OOB:

			function CopyFiles() {
				var fileExplorer = $find("<%=RadFileExplorer1.ClientID%>");
				fileExplorer.copyItems(fileExplorer.get_selectedItems());
			}
			function PasteFiles() {
				var fileExplorer = $find("<%=RadFileExplorer1.ClientID%>");
				fileExplorer.paste(fileExplorer._getCurrentFolderItem())
			}

Clicking on the FileExplorer's Refresh button does not refresh the pager of the control properly when the currently selected page in the grid/listview is bigger than 1.

Steps to reproduce:
1. Open http://demos.telerik.com/aspnet-ajax/fileexplorer/examples/server-sideapi/initialpathandpaging/defaultcs.aspx
2. Navigate to some page (e.g. 3) in the FileExplorer's grid/listview
3. Refresh the control (click the "Refresh" button on the toolbar)

Result: FileExplorer shows the content if the first page, while the pager keeps the state from before the refresh (e.g. 3).

When any new file is uploaded to sub directory, back button stops working.
The controls takes that sub directory as it's root directory.

The current page FileList items are not properly updated when the paging is enabled. Returning to a previously paged folder is properly restored to page 1, but it keeps showing the content of lastly listed page. The issue is reproducible in all explorer modes of the control.

Video - http://screencast.com/t/KVpgADxanuh

The issue is reproducible with RadEditor. When using Lightweight rendering in RadEditor, the FileExplorer's address bar has an inline style with height: 16px rule. This rule should be added only in Classic rendering.

As a side effect, the text in the address box is cut off. 

Possible workaround is to add setting in the web.config to force Lightweight rendering for RadFileExplorer:

<add key="Telerik.Web.UI.FileExplorer.RenderMode" value="lightweight" />

A workaround is to disable the embedded jQuery and use an older version (for example, 1.11.1 which is the previous version the suite used): https://docs.telerik.com/devtools/aspnet-ajax/controls/scriptmanager/disabling-the-embedded-jquery

TreeView context menu remains visible when a permission alert is shown. I should be hidden like the Grid contect menu is.

Video:

https://screencast-o-matic.com/watch/crlYQMV2dzP

Steps to reproduce:

1. Copy a file from the Grid in RadFileExplorer

2. Right click over the same directory in the TreeView and select Paste

Result:

have found similar issue :  http://www.telerik.com/support/pits.aspx#/details/Issue=5296
which look like has been fixed, but unfortunately for following case it doesn't:
We still have performance issue, in following situations:
   - when content root folder contains few (1-5) subfolders
   - one of subfolder contains lot of (200-500) sub-subfolders 

then first time RadFileExplorer  loading to long (aproximatelly 3-5min). after some researching has been found that problem in the method:  

     private bool HasSubFolders(string virtualPath);

which instead of simply check that folder isn't empty (exist any one file or directory)  always construct complete version of the subtree (in the example above - subtree contains 200-500 subfolders, each of them checking for content, permission etc - that is why it takes time). Probable to check that node  HasSubFolders, RadFileExplorer  could execute new virtual method of the FileSystemContentProvider bool HasSubFolders. In that case: FileSystemContentProvider (or inherited classes) will decide that Folder contains SubFolders.

No matter what the current page index is, get_currentPageIndex() will return zero if FileExplorer is used in Thumbnails mode.

Cannot expand configuration on properties panel

Configuration property of FileExplorer is not expandable in DesignTime PropertiesWindow, so its properties cannot be configured.

screenshot - http://screencast.com/t/tdkcjzauLWK

When an image in the list view of FileExplorer is dropped outside the dialog, a duplicate of this image is stuck to the cursor. After selecting another image, the ghost image remains and overlays the upload window.  Follow the attached clip.

Steps to reproduce:
1. Open FileExplorer in Thumbnails mode (or open Editor's Image Manager);
2. Select an image and start dragging it;
3. Drop it outside the dialog;
4. Observe the ghost image on the cursor;
5. Select another image;

Result: The ghost image is not removed and overlays another dialogs.

A JavaScriptError is thrown when FileExplorer with enabled AsyncUplaod is used for multiple files uploading in IE. The message of the error is:
JavaScript runtime error: Object doesn't support property or method 'get_allowMultiRowSelection'

Steps to reproduce:
1. Open http://demos.telerik.com/aspnet-ajax/fileexplorer/examples/asyncupload/defaultcs.aspx in IE10
2. Open the FileExplorer's Upload dialog
3. Select 2 or more files for upload
4. Click the Upload button

Result: A JavaScript error is thrown.

This problem is reproducible with the FileExplorer control only when is set with a thumbnails view-mode. 

When a RadConfirm dialog appears on deleting or another user action is performed a dialog is opened with OK and Cancel button. The localization properties of these buttons can be altered via the RadEditor.Dialogs.resx, although modifying the valu eof the Common_OK property does not change the button's text. 

The following workaround changes the localization used by the RadWindowManager used by the FileExplorer and modifies the value as per to the desired one.

<script type="text/javascript">
	function OnClientLoad(sender, args) {
		var currentLocalization = sender.get_windowManager().get_localization();
		// Change the OK button localization value with "MyCustomOK"
		var myLocalization = currentLocalization.replace("\"OK\":\"OK\"", "\"OK\":\"MyCustomOK\"");

		sender.get_windowManager().set_localization(myLocalization);
	}
</script>

<telerik:RadFileExplorer runat="server" ID="RadFileExplorer1" OnClientLoad="OnClientLoad">
	<Configuration ViewPaths="~/" DeletePaths="~/" />
</telerik:RadFileExplorer>

For large directories we would like to set the initial sort order to descending so we could see the newest files first.

Other times we would like to have the initial sort be by filename descending.

We want to set this declaratively on the control or in the .net code behind on initial page load.

Steps to reproduce:

http://demos.telerik.com/aspnet-ajax/fileexplorer/examples/overview/defaultcs.aspx

       1.  Delete Flower3.jpg
       2.  Rename Flower5 to Flower3

Actual: The image with Flower3 name has changed to the one which was deleted

When trying to drag files with not-so-common extensions to upload, they are not uploaded.

For the time being, you can workaround the issue by using this patch:

<telerik:RadFileExplorer runat="server" ID="RFE1">
    <Configuration ViewPaths="~/" UploadPaths="~/" DeletePaths="~/" SearchPatterns="*.*"/>
</telerik:RadFileExplorer>


<script>
    Telerik.Web.UI.RadFileExplorer.prototype._onAsyncUploadFilesUploading = function (sender, args) {
        var currentDroppedFileType = this._pullNextDroppedFileType();
        if (this._isDropUploadCancelled === true) {
            args.set_cancel(true);
            if (this._isThisLastUploadingFile()) this._finalizeFileDrop();
        }
        this._currentUploadRow = args.get_row();

        if (this._btnUpload != null) {
            this._btnUpload.control.set_enabled(false);
        }
    };
</script>