Internet Explorer does not set a cookie for two-letter domains

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This article was written about products for which Microsoft no longer offers support. Therefore, this article is offered "as is" and will no longer be updated.
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
When you use Internet Explore 6, the SetCookie function does not work for two-letter domains.
This problem is caused by a code change in Wininet.dll. With this code change, the SpecialDomains registry key in KEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\5.0 is not checked.Wininet.dll assumes that a two-letter domain name is a top-level domain. For security reasons, Wininet.dll prevents setting cookies for such domains unless the domain is part of a top-level domain that is listed in the SpecialDomains (REG_SZ) registry key.
To resolve this problem, apply the following hotfix, and then modify the registry to enable the hotfix.

Hotfix information

To resolve this problem, obtain the latest service pack for Internet Explorer 6. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
328548 How to Obtain the Latest Internet Explorer 6 Service Pack

File information

The English version of this hotfix has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.
   Date         Time   Version        Size     File name   -------------------------------------------------------   12-Nov-2001  18:52  6.0.2712.1100  582,656  Wininet.dll				

How to modify the registry to enable this hotfix

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.
  1. Start Registry Editor
  2. Locate and then click the following registry subkey:
    HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\5.0
  3. On the Edit menu, click Add Value, and then add the following registry entry:
    Name: SpecialDomains
    Type: REG_SZ
    Value: lp. rg. ac.
    Note: The value should be the two-letter domain. For example,, where "ca" stands for Canada. However, you must enter the value field as "ac.")
  4. Quit Registry Editor.
To work around this problem, do not use a domain name with less than three letters. You may also want to use HTTP redirects that route requests for www.xx.xx to
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section. This problem was first corrected in Internet Explorer 6 Service Pack 1.

Article ID: 310676 - Last Review: 06/19/2014 13:57:00 - Revision: 3.0

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