Use Sharepoint 2007 sites look and feel in Sharepoint 2010

During upgrade from Sharepoint 2007 to Sharepoint 2010 you may want to preserve look and feel of some of your sites in order to use previous UI version. Most of changes in Sharepoint 2010 were made in UI:

Sharepoint 2010 uses ribbons in UI and it makes its look and feel similar to other Office products. However in your business web application you may still want to have old UI used in Sharepoint 2007. This is quite easy to do. Lets create OTB Publishing Portal site on Sharepoint 2010. Initially it will have new ribbon-style design:

Now in order to revert UI look and feel to the Sharepoint 2007 style we need to run the following program:

   1: using (var site = new SPSite("http://example.com"))

   2: {

   3:     site.RootWeb.UIVersion = 3;

   4:     site.RootWeb.Update();

   5: }

After that the same site will look like this:

No ribbons, no new style – we are back to Sharepoint 2007 now. After playing with old UI lets return back to the modern version:

   1: using (var site = new SPSite("http://example.com"))

   2: {

   3:     site.RootWeb.UIVersion = 4;

   4:     site.RootWeb.Update();

   5: }

And our site again has new UI version with ribbons.