Resolving The "Legacy Issue Detected" Error

While working on SharePoint Migration from 2010 to 2016, I thought it to be smooth because the environment didn’t have any customizations and neither I had any custom solution deployed on it.

So, I started the migration from SharePoint using Content DB. I have migrated Content DB from SharePoint 2010 to 2013. After creating a web application and running “test-spcontentdatabase” PowerShell command (No errors in output), I mounted the content database successfully without any issue.

SharePoint site was working as expected. I have also done the visual upgrade of SharePoint sites without any error. Now, it's time to move to SharePoint 2016. Again, I have to follow the same approach I did in SharePoint 2013.

Moved and restored the Content Database on SQL Server from SharePoint 2013 and created the web applications but when I ran the “Test-Spcontentdatabase” Powershell command, I got an error that I never faced after doing around 10 migrations.

“Legacy Site Detected”

So, I have 2 sites which are still using SharePoint 2010 experience.

Error - “Legacy Site Detected”

Resolution

Follow the below steps.

1. Launch SQL Server Management Studio (SSMS).
2. Connect to the offending content database.
3. Execute the following query,
   
   

   SELECT als.id, als.PlatformVersion, aw.Title, aw.FullUrl, aw.ProductVersion, als.Deleted
   FROM dbo.AllSites als
   INNER JOIN dbo.AllWebs aw
   ON aw.Id = als.RootWebId

4. Locate the entry that doesn’t have product version 15 or Platform version 15.0.35.0. It will look like the below screenshot.
   
   
   

5. Note the GUID associated with the site you identified causing the issue.
   (This will be the id column)
   
   
6. Run the following query using SSMS connected to the content database,
   
   

   UPDATE dbo.AllSites
   SET PlatformVersion = '15.0.35.0'
   WHERE id = GUID'

Verify again by running the query at step 3 and once all platform version is 15.0.35.0, go to SharePoint Server and run the “Test-SPContentDatabase” again.

The legacy issue will be fixed and we are good to go with our SharePoint migration.

Hope this will help you. Happy SharePointing!!!