Consider the following scenario:

  • You have Microsoft SQL Server Analysis Services (SSAS) installed on SQL Server 2017.

  • You configure HTTP access to SSAS through the msmdpump.dll file.

In this scenario, your access to SSAS by using HTTP fails, and you receive an error message that resembles one of the following:

Error message: XML parsing failed at line line_number, column column_number: DTD is prohibited.

"File System error", the following error occurred while reading from the file "Compressed stream"


This fix is included in the following update for SQL Server:

Cumulative Update 9 for SQL Server 2017

After you install this update, follow these steps to resolve this issue:

  1. Pause the IIS application pool.

  2. Copy the new msmdpump.dll file to the IIS webserver. For information about how to do this, see "Step 1: Copy the MSMDPUMP files to a folder on the Web server" of the Configure HTTP Access to Analysis Services on IIS 8.0 topic on the Microsoft Docs website.

  3. Restart the IIS application pool.

About SQL Server builds

Each new build for SQL Server contains all the hotfixes and security fixes that were in the previous build. We recommend that you install the latest build for your version of SQL Server:

The latest build for SQL Server 2017


Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.


Learn about the standard terminology Microsoft uses to describe software updates.

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