Hi guys I'm trying to create a site collection by UI from central admin and by using powershell commands as well. But I'm getting object reference not set to an instance of an object error. By searching logs we have found following:

08/28/2015 12:31:27.05 w3wp.exe (0x1B84)                       0x2248  SharePoint Portal Server              User Profiles                                 cm6y     High       User Profile Application Proxy failed to retrieve partitions from User Profile Application: Microsoft.Office.Server.UserProfiles.UserProfileApplicationNotAvailableException: UserProfileApplicationNotAvailableException_Logging :: UserProfileApplicationProxy.ApplicationProperties ProfilePropertyCache does not have 65a59ea4-eed4-4b52-b8b5-4df94f9c14b2     at Microsoft.Office.Server.Administration.UserProfileApplicationProxy.get_ApplicationProperties()     at Microsoft.Office.Server.Administration.UserProfileApplicationProxy.get_PartitionIDs()     at Microsoft.Office.Server.Administration.UserProfileApplicationProxy.IsAvailable(SPServiceContext serviceContext)                9860289d-e383-60ef-1b52-74c04209f998

08/28/2015 12:31:27.06 w3wp.exe (0x1B84)                       0x2248  SharePoint Foundation                 General                                ajlz0                High

                Getting Error Message for Exception System.Web.HttpUnhandledException (0x80004005): Exception of type 'System.Web.HttpUnhandledException' was thrown. ---> System.NullReferenceException: Object reference not set to an instance of an object.     at Microsoft.SharePoint.Administration.SPContentDatabaseCollection.FindBestContentDatabaseForSiteCreation(IEnumerable`1 contentDatabases, Guid siteIdToAvoid, Guid webIdToAvoid, SPContentDatabase database, SPContentDatabase databaseTheSiteWillBeDeletedFrom)     at Microsoft.SharePoint.Administration.SPContentDatabaseCollection.FindBestContentDatabaseForSiteCreation(SPSiteCreationParameters siteCreationParameters, Guid siteIdToAvoid, Guid webIdToAvoid, SPContentDatabase database, SPContentDatabase databaseTheSiteWillBeDeletedFrom)     at Microsoft.Shar...       9860289d-e383-60ef-1b52-74c04209f998

Please suggest what exactly is happening into the server.

Any help will be apprec

Did you try to restart the user profile application service? Also try to recreate user profile service if you still have issues.

Hi

From the error message, it seems that the authentication for security token service in IIS had "Forms" and "ASP.NET impersonation" enabled. This was preventing the users identity to be passed to the security token service and the token service was unable to generate tokens properly.Try to do the following steps:

Open up the  IIS Manager on the SharePoint server

• Expand Sites
• Expand SharePoint Web Services and select SecurityTokenServiceApplication
• Double click on Authentication(under IIS)
• Disable Forms Authentication and ASP.NET impersonation 
• Confirm that only Windows and Anonymous Authentication are enabled
• IISRESET 

For detailed information, refer to the following article:

http://blogs.technet.com/b/manjesh/archive/2011/02/06/sharepoint-2010-unable-to-start-the-user-profile-synchronization-service.aspx

Besides, here are some similar issue post:
http://stackoverflow.com/questions/4428552/user-profile-application-proxy-failed-to-retrieve-partitions-from-user-profile-a

http://bernado-nguyen-hoan.com/2012/08/30/nullreferenceexception-at-microsoft-office-server-administration-userprofileapplicationproxy-get_applicationproperties/

Best Regards

Lisa Chen