The [SharePoint] web application is configured with claims authentication mode however the content database you are trying to attach is intended to be used against a windows classic authentication mode.

pointshare.plComment (0)Posted in SharePoint

Problem

Category        : Configuration
Error           : False
UpgradeBlocking : False
Message         : The [SharePoint] web application is configured with claims
                  authentication mode however the content database you are
                  trying to attach is intended to be used against a windows
                  classic authentication mode.
Remedy          : There is an inconsistency between the authentication mode of
                  target web application and the source web application.
                  Ensure that the authentication mode setting in upgraded web
                  application is the same as what you had in previous
                  SharePoint 2010 web application. Refer to the link
                  "http://go.microsoft.com/fwlink/?LinkId=236865" for more
                  information.
Locations       :

Rozwiązanie

$(Get-SPWebApplication http://pointshare.pl).MigrateUsers($true)

lub 

Convert-SPWebApplication -Identity http://pointshare.pl -From Legacy -To Claims -RetainPermissions