Recently there has been a 'vulnerability scare' involving Internet Explorer. As I understand it, the advice was to increase security levels to maximum.
Internet Explorer > Tools > Internet Options, Security tab, Internet Globe, if "Custom level" settings have been set, change to Default level, then increase the slider to High.
If your settings are set to high, perhaps this is the problem.
Can you access Windows Live or these other accounts in any other browser, eg Firefox, Chrome, Opera, SeaMonkey, etc?
Mark
I am running a recent installation of Windows 7 with IE8.
When I attempt to log into Windows Live or any of my Microsoft Browser accounts I receive a message Certificate Errors Navigation Blocked. I am running Microsoft Security Essentials. There is a code 80072F8F. I have run the malicious software removal program. I have read the MS message about certificate errors. I have performed the Windows Update error 80072f8f fix. I have run Restore. All without resolving the problem. The block is not allowing my computer to update.
When I enter Tools - Internet Options - Content - Certificates - Publishers - Untrusted Publishers I discover two files listed as Microsoft Corp. Verisign Commercial Software Publisher internet option 1/30/2002 and content 1/31/2002.
Messages I have read in other parts of the forum do not seem to address the problem. Others seem to be experiencing similar problems.

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