Over the past week I have had numerous people tell me they can no longer launch hyperlinks into Internet Explorer. If you recently installed an Adobe update and/or removed Google Chrome web browser, you may have this problem if you use Internet Explorer. Many popular pieces of software such as Adobe Reader bundle Google Chrome in the installation. While bundled software usually can be unchecked in the installer, this can can go unnoticed.
All of the users experiencing the problem were attempting to launch a hyperlink in Microsoft Outlook. They would receive an error such as "This operation has been canceled due to restrictions in effect on this computer." This kind of behavior can be traced to a network firewall security setting, or even resolved by setting program defaults in the control panel. Neither were an issue or fix.
The problem appears to be related to Google Chrome's uninstaller failing to reassociate .html and .htm registry classes back to Internet Explorer. There is a simple fix, and hopefully will be addressed by Google.
Expand HKEY_CLASSES_ROOT.html. Modify the default value key from ChromeHTML to htmlfile. Do the same for HKEY_CLASSES_ROOT.htm and change the default value to htmfile.
Close and reopen Outlook and you should be able to launch hyperlinks again.