When you attempt to view the source HTML of a web page in Internet Explorer it may not be displayed for several reasons. This article describes some of the common causes of this problem.

There are a number of reasons that the Internet Explorer View Source feature may not function correctly, below is a list of the most common causes.

1. Temporary Files Full
   When the Internet Explorer disk cache becomes full it may stop the View Source function from working. To resolve, open Internet Explorer and click "Tools" > "Internet Options" > "Delete Files".
   
   
2. Cookie Folder Location
   This issue can also occur if your Cookies folder is located on an NTFS partition and you do not have at least Change permissions for the Cookies folder. To resolve, make sure your account has sufficient permissions on the Cookies folder.
   
   
3. Missing Notepad.exe
   The View Source function uses Notepad to display the HTML, if "notepad.exe" is missing from the Windows directory then it will not work. To resolve, ensure a copy of Notepad.exe is in the Windows directory.
   
   
4. Incomplete Page Download
   If you press the ESC key before the page has completed loading then the "View Source" menu item may not be displayed.
   
   
5. View Source Restriction
   The View Source function may have been restricted by your Administrator. To resolve, see the "NoViewSource" registry value in Internet Explorer Restrictions.
   
   
6. Invalid Temporary Directory
   You may also receive this error if the path specified for the TMP environment variable is invalid. To resolve, make sure that the TEMP directory is a valid directory and that there is sufficient space on the drive.
   
   
7. Invalid View Source Program
   If you have specified an alternate program to view the source code (see Use an Alternate Source Viewer with Internet Explorer). To resolve, make sure that the alternate viewer is valid and operational.
   
   
8. Right-click disabled by Web Page
   Some web pages may implement a restriction to stop visitors from right-clicking on the web page. The source may still be viewed by clicking the main "View" menu, then "Source".

Disclaimer: Modifying the registry can cause serious problems that may require you to reinstall your operating system. We cannot guarantee that problems resulting from modifications to the registry can be solved. Use the information provided at your own risk.