This hotfix applies to Microsoft SQL Server 2012 Reporting Services (SSRS 2012) and SQL Server 2014 Reporting Services (SSRS 2014).
Consider the following scenario:
You have a report that contains only one text box in Microsoft SQL Server 2012 Reporting Services (SSRS 2014).
You set the expression for the text box to Chr (n), where n is a C0 control code (nonprintable code) value other than one of the following:
9 (U+0009 TAB),
10 (U+000A LINE FEED),
13 (U+000D CARRIAGE RETURN),
C0 control character value (0 to 31).
Render the report, export it to Excel (Office Open XML format - xlsx), and then open the Excel workbook.
If the report contains C0 control codes in this scenario, the Excel OpenXML rendering extension that’s included in SSRS 2012 produces workbooks that Excel recognizes as invalid.
Note The issue also occurs in SSRS 2008 R2.
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:
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.