Upgrading to 4.2 Breaks FaceBook widget

I have a 4.0 site that I'm attempting to upgrade.

First I ran the upgrade to 4.1 SP3.  That seems to work great, no problems.

Then I run the 4.2 Upgrade.  That also seems to work OK, except after I complete the upgrade and verify my license, when it redirects to the home page of my site, I get this error:

Parser Error Message: Could not load file or assembly 'Telerik.Sitefinity, Version=4.1.1574.0, Culture=neutral, PublicKeyToken=b28c218413bdf563' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)

I've run the entire process twice and have had the same problem both times.  If I remove the LikeBox widget from my page template, my site displays OK.

What's the best fix for this?  How can I manually upgrade the FB widget?  I'm not the one who originally built the site, but I believe that the FB widget came from the Charity Starter Kit.  Is it not compatible with 4.2?

thanks - Jason

Add in assembly binding to the web.config

The control is compiled under an older version of the DLL so assembly binding will route it over to your version (just follow the instructions to add in the proper DLL versions)

Thanks - that fixed that problem.

However, when I go into my page template to re-add the FB widget, I'm having trouble persisting the settings.  I can add widget (with the default Telerik FB page), but when I try to change the widget settings they don't stick.  No errors, but no changes either.

If I switch to the advanced mode of the widget editor, I can change some of the text settings and save them.  But trying to change any of the boolean values (Show Header, Show Stream) still doesn't work.

Hello Jason,

Facebook widget is available with corporate starter kit available with Sitefinity 4.2 SDK. I have added it to a project and all advanced properties were working. Can you try this widget and see if it the same as the one you use? If the one you use is different from the one available with the corporate starter kit please open a support ticket and send me the widget so I can examine it.

Best wishes,
Stanislav Velikov
the Telerik team

How do I use the new widget with an existing project?  Do I just install the 4.2 SDK, or are there additional steps I need to take?  How can I tell if I'm using the "new" widget or not?

Hello Jason,

You should install the sdk to get the widget project. Add this project to the solution you want to use it with.

To tell the difference from the old widget you can register it in a different toolbox section(for example navigation).
You can take the registration details from App_Data/SItefinity/TollboxesConfig on the  project from which the widget is part of.

Greetings,
Stanislav Velikov
the Telerik team