Hi,

after starting an eDiscovery search the mailbox dismounts unexpectedly and in the evenlog I am getting the following error:

Source: MSExchangeIS
EventID: 1002

Event details:

System.NullReferenceException at Microsoft.Exchange.Server.Storage.AdminInterface.AdminRpcServer.AdminRpcMultiMailboxSearchBase.IsPropertyInFullTextIndex(UInt32 errorLID, Guid mdbGuid, ExtendedPropertyColumn extendedColumn, StorePropTag& nonFullTextPropTag)

Thanks for help.

So sounds as though you may have a bad index, check out this post http://blogs.technet.com/b/exchange/archive/2014/10/03/those-pesky-lazy-indice

Whats your CU l