We have created a KB article where a possible approach to achieve image resizing before the upload is suggested. You can find it at https://www.telerik.com/support/kb/aspnet-ajax/upload-(async)/details/resize-images-client-side-with-html5-before-uploading-with-radasyncupload

The article describes a straightforward way on how to change the uploaded image dimensions. You can further improve and modify the logic in the _uploadFile function to allow the user to define the new dimensions or use a tool to allow the users to modify the image.

Workaround: 

function encodeRowContent() {
    var asyncUpload = $find('<%= RadAsync_FileUpload.ClientID%>');
    var $ = $telerik.$;
    asyncUpload._updateRowContent = function (row, inputValue) {
        var $progress,
            $content = $("<span class='ruUploadProgress'>" + $telerik.htmlEncode(this._getFileName(inputValue)) + "</span>");

        $(row).removeClass("ruSelectWrap")
                .addClass("ruFileLI ruUploading")
                .prepend("<span class='radIcon'></span>");

        if (this._isManualUpload())
            $content.addClass("ruUploadOnHold");

        if (this._enableInlineProgress) {
            $progress = $('<span class="ruFileProgressWrap"><span class="ruFileProgress"></span></span>');
            $content.append($progress);
        }

        $('.ruFakeInput, .ruBrowse', row).remove();
        $(".ruFileWrap", row).append($content); // Replace fake input
    }
}

Sys.Application.add_load(encodeRowContent);

The user should be able to determine by which criteria the validation failed (size or extension).

Hi Telerik Team,
is it possible to implement the feature into the uploadmodule control , that you can open the uploaded files per Double-Click.
We want to use the control to create offers and we want to give the users the option to upload files - that works wonderful.
But the following editors of the offers don`t have the chance to open the "attached" files.

Thank you very much.
Best Regards,

Jan Brandenburger

Documentation says Firefox should be ok with LastModifiedDate, but it's not.  It's consistently being set to 1/1/0001 12:00:00 AM, which is not useful.

Happens in any RadAsyncUpload example if you look at the value for LastModifiedDate in the AsyncUploadedFile objects.

Works fine in Chrome, Edge.  Fails in Firefox for Mac or Windows.

This issue is observed only in R1 2020. The solution is to not disable the FileAPI.

Reproduction steps:

<script>
    Telerik.Web.UI.RadAsyncUpload.Modules.FileApi.isAvailable = function () { return false; };
    Telerik.Web.UI.RadAsyncUpload.Modules.Flash.isAvailable = function () { return false; };
    Telerik.Web.UI.RadAsyncUpload.Modules.Silverlight.isAvailable = function () { return false; };
</script>
<telerik:RadAsyncUpload runat="server" ID="RadAsyncUpload1" ></telerik:RadAsyncUpload>

Recently, Chrome version has been updated our all the user’s system as 117.xxx.xxx.

After updating the Chrome version and RadAsyncUpload is not working and getting the below error message. So, user unable to perform any upload action on this.

This is control using in production live application and it affecting our day-to day business.

Please provide your solution as soon as possible.

Error – Message :

Uncaught Error while uploading, <div></div><pre>{"fileInfo":{"FileName":"README.md","ContentType":null,"ContentLength":5798,"DateJson":null,"Index":0}, "metaData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}</pre>

Hi,

When we upload files using RadAsyncUpload control, will get the uploaded file along with the two images.
1. check image
2. cross image (to delete the uploaded file)

my question is can we overwrite these images in our  application.

when deleting files from radasyncupload via the "built-in" delete button, "get_fileName()" method in both the upload_removing and upload_removed events returns correct data. However, when deleting files via the api, the get_fileName() method returns bad content.

built-in button something like:
document.pdf

api something like:
document.pdf<span class="ruFileProgressWrap"><span class="ruFileProgress"></span></span>

to reproduce: 
1. run attached web form. select file for upload. click remove button. view console. all good.

2. click the "delete via api" checkbox to enable. select another file. view console. bad.