The digital signature is lost when you use an earlier version of an Office program to open a file that was saved in a 2007 Office program


Important This article contains information about how to modify the registry. Make sure that you back up the registry before you modify it. Make sure that you know how to restore the registry if a problem occurs. For more information about how to back up, restore, and modify the registry, click the following article number to view the article in the Microsoft Knowledge Base:
256986 Description of the Microsoft Windows registry

Symptoms


In Microsoft Office Word 2007, you save a document that has a digital signature in the Word 97-2003 Document (*.doc) format. However, when you open the document in Microsoft Office Word 2003, in Microsoft Word 2002, or in Microsoft Word 2000, the digital signature is lost.

Note This problem also occurs in Microsoft Office Excel and in Microsoft Office PowerPoint.

Cause


This problem occurs because the digital signature format in Microsoft Office Excel 2007, in Microsoft Office PowerPoint 2007, and in Word 2007 is incompatible with the digital signature format in earlier versions of these programs.

Resolution


Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.

To resolve the problem in Word 2007, configure the
Signature registry subkey. To do this, follow these steps:
  1. Exit Word 2007.
  2. Click Start, click Run, type regedit, and then click
    OK.
  3. Click the following registry subkey:
    HKEY_CURRENT_USER\Software\Microsoft\Office\12.0\Common\Signatures
    Note If the Signature subkey does not exist, you must create it. To do this, follow these steps:
    1. Right-click Common, point to
      New, and then click Key.
    2. Type Signature, and then press ENTER.
  4. Right-click Signature, point to
    New, click DWORD Value, and then press ENTER.
  5. Right-click the new entry that you created in step 4, and then click Rename.
  6. Type XPCompatibleSignatureFormat to name the entry, and then press ENTER.
  7. Right-click the value, and then
    Modify.
  8. In the Edit DWORD Value dialog box, type
    1 in the Value data box, and then click
    OK.
Note This resolution also resolves the problem in Excel and in PowerPoint.

More Information


If you save a Word 2007 document that has a digital signature in the Word Document (*.docx) format, you receive the following error message when you open the Word 2007 document in Word 2003:
This file was created and digitally signed in a newer version of Microsoft Word. The file has been converted to a format you can open, but the digital signature was lost.
The procedure that is described in the "Resolution" section does not resolve this problem.