SharePoint 2010 site to 2013 using DB detach and attach method

Question

I followed this

http://www.sharepointdiary.com/2013/09/migrate-from-sharepoint-2010-to-2013-step-by-step.html

Everything is fine (not error during upgrade either). However, user's in the permission groups still shows domain\username instead of claim based. If i add a new user then it shows i:0#.w|domain\davidhassel01

Since it's a 2013 site so the web app is already claimed based. I can't read the SP groups using powershell script.

The SP 2010 is classic and i can't just change it to claims because it's production site.

Any idea on how to fix this issue?

Answer 1

After working on this for past 3 days finally following steps helped

1. I deleted all the users from _layouts/15/people.aspx?MembershipGroupId=0
2. I then copied all the SharePoint groups from the source site to target site

Now all the users have proper permissions and they appear with the claim token.

Thanks Trevor for looking into this.

Answer 2

Re-run Convert-SPWebApplication. It is safe to re-run this.