Microsoft SQL Server 2012 Reporting Services (SSRS 2012) or SQL Server 2014 Reporting Services (SSRS 2014) may fail with the following IsolatedStorageException exception when the subscriptions that are exported to Excel worksheets are larger than 10 megabytes (MB).
System.IO.IsolatedStorage.IsolatedStorageException: Unable to determine the identity of domain.
Each new cumulative update for SQL Server contains all the hotfixes and all the security fixes that were included with the previous cumulative update. Check out the latest cumulative updates for SQL Server:
Service pack information for SQL Server 2012 To resolve this problem, obtain the latest service pack for Microsoft SQL Server 2012. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
2755533 How to obtain the latest service pack for SQL Server 2012
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.