You install Internet Information Services (IIS) 7.5 on a computer that is running Windows 7, or Windows Server 2008 R2.
You host some Portable Document Format (PDF) documents on an IIS Web site on this computer.
You have a client computer that has the Adobe PDF Reader plug-in enabled on a Web browser.
You use this Web browser to open one of the PDF documents that is hosted on the IIS Web site.
In this scenario, you cannot open the PDF document. Additionally, the Web browser may stop responding.
You may still be able to open other PDF documents on this IIS Web site when this issue occurs.
This issue does not affect all versions of the Adobe PDF Reader plug-in.
This issue occurs because of a design change in IIS 7.5.
When you try to open a PDF document on an IIS Web site, the Adobe PDF Reader plug-in sends a request that includes multiple byte ranges to IIS 7.5. If the union of the multiple byte ranges is a single byte range, the response from IIS 7.5 contains the byte ranges merged into a single byte range (also known as a merged byte-range request). The response to this single byte range does not include the multipart/byteranges content type. However, the multipart/byteranges content type is expected to be included in a response to a merged byte-range request. This behavior causes the Adobe PDF Reader plug-in to handle the response incorrectly. Therefore, the PDF document cannot be opened.
Note The multipart/byteranges content type is included in a regular multiple byte-ranges response.
To resolve this issue, apply this hotfix on the computer that is running IIS 7.5.
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing the problem described in this article. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.
Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site:
Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
To apply this hotfix, you must be running Windows 7, or Windows Server 2008 R2.
You must restart the computer after you apply this hotfix.
Hotfix replacement information
This hotfix does not replace a previously released hotfix.
The global version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.
Windows 7 and Windows Server 2008 R2 file information notes
Important Windows 7 hotfixes and Windows Server 2008 R2 hotfixes are included in the same packages. However, hotfixes on the Hotfix Request page are listed under both operating systems. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows 7/Windows Server 2008 R2" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.
The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information for Windows Server 2008 R2 and for Windows 7" section. MUM and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintaining the state of the updated component. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.
For all supported x86-based versions of Windows 7
For all supported x64-based versions of Windows 7 and of Windows Server 2008 R2
For all supported IA-64-based versions of Windows Server 2008 R2
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:
824684 Description of the standard terminology that is used to describe Microsoft software updates
Additional file information
Additional file information for Windows 7, and for Windows Server 2008 R2
Additional files for all supported x86-based versions of Windows 7
Windows 7 Enterprise, Windows 7 Home Premium, Windows 7 Professional, Windows 7 Ultimate, Windows HPC Server 2008 R2, Windows Server 2008 R2 Datacenter, Windows Server 2008 R2 Enterprise, Windows Server 2008 R2 Standard, Windows Web Server 2008 R2, Microsoft Internet Information Services 7.5