I have been running Internet Explorer 7.0 on Windows Vista for several
months and it was working fine. But today I just installed the "Security
Update for Windows Internet Explorer 7 (KB931768)" and that caused IE7 to
stop working.

After I installed the update and restarted Windows, IE7 will no longer
start. Now when I double-click the icon or run iexplore.exe, the web browser
window flashes quickly on the screen and then disappears. Then this error
message dialog box appears.

----------------------------------------------------------------------
File Download - Security Warning
Do you want to save this file?
Name: navcancl
Type: Unknown File Type, 2.64KB
From: ieframe.dll
Save Cancel
----------------------------------------------------------------------

temporarily, I have three ways to fix it:
1. retore Vista or uninstall the patch
2. run IE as Administrator ( which, as a matter of fact, disable the
protection mode)
3. in IE Options->Securities->disable Protection Mode.