Allow active content to run in files on My Computer - Windows XP Service Pack 2

When you encounter a Web page that is trying to run active content on your computer, you will receive a message prompting you to indicate whether you want to allow this. If you are certain that you want to allow the Web page to run ActiveX controls or scripts, click Yes in the message box. By clicking Yes, you allow the active content to run on the Web page you’re viewing, but only on that occasion. If you leave the page and return to it later, you will receive the message again (because you did not change the setting that allows active content to run on your computer).

WORKAROUND

In some cases, say when you're building and testing a webpage locally (Local Machine Zone), you may still see the Information Bar when the web page executes any script, initiates a Pop-up windows, or a download. For testing purposes, one needs to follow any of these workarounds:

• Rename the .HTM file to .HTA (Example.. Index.HTM to Index.HTA and test the file locally). HTA files have more privileges than the HTM files, can run active content on Local Machine by default.
  -or-
   
• add the Mark Of The Web code such as <!-- saved from url=(0023)http://www.contoso.com/ --> to a Web page, where the (0023) value is the string length of your URL that follows it and Contoso is the name of your Web site.

The above is an extract from Local Machine Zone Lockdown - Developer Implications. See page for more information about the two workarounds above.
To totally disable the Local Machine Zone restriction (for running Active Content) (not recommended, though) for valid reasons, read below:
To allow any Web site to run scripts and ActiveX controls on your computer:
In Internet Explorer, on the Tools menu, click Internet Options. On the Advanced tab, scroll down to the Security section of the list. Select the Allow active content to run in files on My Computer check box, and then click OK.

To accomplish this via the Registry, modify the following registry value:
HKCU \ Software \ Microsoft \ Internet Explorer \ Main \ FeatureControl \ FEATURE_LOCALMACHINE_LOCKDOWN
In the right-pane, create a new REG_DWORD named iexplore.exe and set it to 0
Values:

0 - Allows a Web page to run active content in your computer
1 - Disallows a Web page from running active content in your computer

To allow any CD to run scripts and ActiveX controls on your computer:
In Internet Explorer, on the Tools menu, click Internet Options. On the Advanced tab, scroll down to the Security section of the list. Select the Allow active content from CDs to run on My Computer check box, and then click OK.