PDF files don't display for some sites on Internet Explorer

 PDF files don't display for some sites when you use Internet Explorer with the embedded Adobe Acrobat or Adobe Reader PDF viewer.

This issue is only applicable if you are using Adobe Acrobat/Reader 10.0.0, 10.0.1, 9.4.2, or 9.4.3. Later patch releases address this issue.

This issue only occurs in the following situations:

  • The filename part of the URL path does not have a '.pdf' extension (for example, it has .aspx or .php). This case is more common when you're looking at a statement or bill from a utility or financial institution. 
  • The Content-Type (mime-type) header contains additional information past the MIME type (for example, "application/pdf;charset-UTF-8," which is common for web applications. 


Do one of the following:

  • For the company owning the server: Change the MIME type to "application/pdf."
  • For the company owning the server: Change the URL to have extension ".pdf."
  • For the client running Internet Explorer: add a registry item using the Windows Registry Editor, as described below:

Important note regarding registry entries

Adobe does not recommend manually adjusting the Windows registry. Proceed with caution, and only if you feel confident about editing it. Incorrectly modifying the Windows registry can result in serious Windows or application performance issues. Adobe Technical Support cannot support any issues caused by modifications to the Windows registry.

 **Back up your registry before proceeding.

  1. Choose Start > Run.

  2. Type regedit and click OK.
  3. Navigate to the following location: HKEY_LOCAL_MACHINE\SOFTWARE\Classes\MIME\Database\Content Type\
  4. Select Content Type.
  5. Choose Edit > New > Key.

  6. Name the key as it corresponds to the content type sent by the server. For example, if the content-type from the server is "application/pdf;charset=UTF-8," which is the most common, name the key that: application/pdf;charset=UTF-8.

  7. Select the new key that you just named.
  8. Choose Edit > New > String Value.
  9. Name the new String Value "AdobeMimeTreatAs."
  10. Double-click the newly named String Value "AdobeMimeTreatAs."
  11. In the Edit String window, type the following String value:


  12. In the Edit String window, click OK.
  13. Choose File > Exit.