Good news, we've just released version 16.1.1 of the ASP.NET AJAX Control Toolkit today. This release includes new features and several bug fixes.
Continuous Integration - AppVeyor

In the last release, we moved this open source project from CodePlex to GitHub: ASP.NET AJAX Control Toolkit - New Release v16.1 and GitHub Hosted!
Hosting ASP.NET AJAX Control Toolkit on GitHub now provides us new benefits. One of the major improvements is AppVeyor CI integration which allows to:
That last statement means that you no longer have to wait for NuGet packages or build hotfix by yourself. Simply download the latest build from AppVeyor and update your project.
v16.1.1 - Major Changes
Tabs Custom CSS Fix
We've fixed a major issue with Tabs regression by introducing a new property: CssTheme.
If you set the CssClass attribute to the TabContainer then please make sure the CssTheme attribute is set to None. By default, it is set to XP, so no further actions are required if you run Tabs with default style settings.
AjaxFileUpload New Setting: Temp Folder Path
A new setting was added to AjaxFileUpload that allows specifying temporary folder path. This setting is configured via Web.config:
<ajaxControlToolkit
...
tempFolder="~/Temp"/>
This parameter allows AjaxFileUpload to operate in a Medium trust environment, if set to an application (sub)folder. You can run the AjaxFileUpload control in a Web farm too just make sure that this path is set to a network folder.
HtmlEditor Deprecated
Starting with this v16.1.1 release, we have deprecated the HtmlEditor in favor of HtmlEditorExtender. To avoid breaking changes we will still include the HtmlEditor control in the release.
However, the HtmlEditorExtender is a much better option and we recommend that you use it instead of the deprecated HtmlEditor. For example, the HtmlEditorExtender:
- has improved security because it sanitizes user input
- is smaller in size
- and has a customizable toolbar
Please read this blog post to learn more about HtmlEditorExtender.
ValidatorCalloutExtender is Compatible with Unobtrusive Validation
Unobtrusive validation was introduced in .NET Famework 4.5 release. This validation uses HTML5 data-* attributes instead of JavaScript code emitted to a page.
The ValidatorCalloutExtender can now work with the latest versions of the full .NET framework (.NET 4.5+).
Helpful links
Helpful documentation articles are available here:
Download v16.1.1
You can download the latest release here:

Click the download button above and the get the latest bits.
Or use the Nuget package: ASP.NET AJAX Control Toolkit Nuget package
Or download the installer and/or source from GitHub:
Try DevExpress ASP.NET
We’d like to thank you for installing the DevExpress Edition of the AJAX Control Toolkit and look forward to your feedback as you begin using it.
When we took over the fabulous ASP.NET AJAX Control Toolkit, our goal was to reach those web developers who want to use great web user interface controls for their web projects and DevExpress ASP.NET provides that and much more.
Try the free DevExpress 30 day trial.
Email: mharry@devexpress.com
Twitter: @mehulharry
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