OK, scenario -

2 websites were created using vwd 2005 with the .net 2.0 (XP IIS5.x)

I now have them on another machine with vwd 2008 and .net 3.5. (Vista IIS7)

1 website (hosted at godaddy) needs .net 2.0, the other at re-invent.com can use 3.5. - all according to their respective web sites.

Can I use the newest control toolkit's extenders with both and expect them to work after uploading? If not, how can I switch between the 2 locally when developing?

I hope this makes sense.... 

The Ajax Control toolkit should work on both. As long as you have the ajax library referenced, it should be good.

On the godaddy site, you will need to reference the ajax library manually, the libary can be downloaded from here: http://www.microsoft.com/downloads/details.aspx?FamilyID=ca9d90fa-e8c9-42e3-aa19-08e2c027f5d6&displaylang=en

You take the library the installation file installed and put it in your Bin folder of your website.
On the re-invent.com site, you should already have access to the AJAX controls. The AJAX extension was included in the .net framework 3.5.

 If you are using VS2008, you should be able to use the retargeting feature. This feature allows you to design your webapplication for .net 2.0 and then "retarget" it to 3.5 to see if it works with .net framework 3.5.

 Are the Ajax extensions included with 3.5 the same as what is in the link? The one in the link seems dated (3/2/2007).

Also, How can I, or can I use the different versions of the extensions? Can I switch between them while developing? And, lastly, what is the
Microsoft Ajax Library 3.5 found here http://asp.net/ajax/downloads/ and how does it fit in with the rest of the stuff...

Just trying to sort this all out and be able to develop one site with .net 2.0 and another with 3.5...with either Control Toolkit. 

Hi Ksasp,

ksasp:

Are the Ajax extensions included with 3.5 the same as what is in the link? The one in the link seems dated (3/2/2007).

No.  This is only a link of ASP.NET 2.0  AJAX Extension V1.0.  If your application works on .NET Framework 2.0,  you should first install the Extension.   Otherwise , your application works on .NET Framework, you need not install the Extension individually.  The Extension will be installed automatically when you install .NET Framework 3.5.  

If AJAX Control Toolkit controls are contained inside your application, you should make sure that your application referenced to right AjaxControlToolkit.dll.  Actually AJAX Control Toolkit is divided into two versions for .NET Framework 2.0  and .NET Framework 3.5.

ksasp:

Also, How can I, or can I use the different versions of the extensions? Can I switch between them while developing? And, lastly, what is the Microsoft Ajax Library 3.5 found here http://asp.net/ajax/downloads/ and how does it fit in with the rest of the stuff...

Please reference to Gentoobox's reply.

Here are the documents for ASP.NET AJAX Extension  and AJAX Control Toolkit.  Also you can find some useful video tutorials here.

Best regards,

Jonathan