This is part of a series on SharePoint Health Report issues, because I can never remember what to do about them.
The warning looks like this:
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 :
The obvious solution is that the warning is correct and there is a configuration mismatch:
Either the ContentDatabase was migrated or the authentication scheme for the WebApplication was changed: In this case, you probably forgot to run
Convert-SPWebApplication to convert all logins to claims.
On the other Hand, it is possible that
Convert-SPWebApplication has been run properly but not everything was converted properly: Trevor Seward explains that the rule to create above message will simply report that
SELECT TOP 1 [tp_SiteID],[tp_Login] FROM [UserInfo] WITH (NOLOCK) WHERE tp_IsActive = 1 AND tp_SiteAdmin = 1 AND tp_Deleted = 0 and tp_Login not LIKE 'i:%'
In his post, Trevor explains that deleted AD users are not converted and could be the root cause of the
In my case someone added an AD-Group as SiteCollection administrator. For one this simply does not work
and also – as AD-Group claims start with
c: this will also result in above warning.
In any case: Removing the offending entries (using PowerShell or manually from the UI – do not delete things from the ContentDatabase!) will solve the problem.