V3 UI on 2013 Farm

Question

In the farm I'm looking at, there are some old archive-like sites that were upgraded from a 2007 farm to a 2010 farm but still have the V3 UI. Some of them are heavily branded, not actively used, some even read-only, but they are still searchable and available. There is no way any effort will be put into updating them to a new look.

Now it's time to look at migrating this same farm to SP2013. As we know, the SP2013 farm has both the 14 and the 15 hive, and we can move 2010 Content DBs to the 2013 farm without upgrading them to the 15 hive.

My question is: Will I be able to keep these webs with the V3 UI on the 14 hive of the new 2013 farm? Has anyone done it? Any caveats I should be aware of?

Answer 1

Finally had some time to test it and here's the sad result from a Test-SPContenDatabase PowerShell command. It is not blocking of the upgrade, but the upgrade process upgrades all sites to an SP2010 look, so there's no way of keeping the V3 look.

I've also tried to update the SPWeb's UIVersion field after the upgrade, but no luck with either PowerShell or SPM.

Category : LegacyUIDetected Error : True UpgradeBlocking : False Message : The site [/] is still referencing SharePoint 2007 UI. Remedy : The site located at [/] in the database [WSS_Content_staging_12345] is using SharePoint 2007 UI which is no longer supported and may cause visual errors or block functionality. We strongly recommend that you run Visual Upgrade on the site and verify the site is working correctly before proceeding. Otherwise, we will force all sites using SharePoint 2007 UI to visually upgrade to the 2010 UI as part of the database upgrade process.