When the information security agency of a major government bans a product, you know the maker is in trouble.

That's what happened to Microsoft (NASDAQ:MSFT) this week. Germany's Federal Office for Information Security issued a strongly worded statement (though love songs and lullabies also sound harsh in German) discouraging the use of Microsoft's Internet Explorer (IE) Web browser.

The warning covers pretty much any Windows-based computer of recent enough vintage to connect to the Internet, and it explicitly mentions IE vulnerabilities being exploited in the recently unveiled hack-attacks that made Google (NASDAQ:GOOG) threaten to pull out of China. Microsoft is working on a software fix, but mainly says that everyone should just get with the times and upgrade to IE8 already.

But the Germans see a wider problem until Microsoft comes up with a general fix for the leaky code. The agency doesn't provide a list of alternatives, but there are plenty: The open-source Firefox browser runs on nearly any platform and is gaining ground on Explorer; Google has its Chrome browser, based on the same foundation as Apple’s (NASDAQ:AAPL) Safari -- and Safari runs just fine on Windows, too. Behind these major players, there's a cast of thousands vying for a place in the spotlight.

This could be their chance. Microsoft's browser has more security holes than the Kansas City Chiefs, but I've never seen an influential government agency put the product down so publicly -- and the fact that Microsoft sort of agrees with the warnings is equally troubling. Chrome is quietly becoming a force to be reckoned with, and I only wish the Mozilla Foundation behind Firefox would go public.

Microsoft fought very hard to make Internet Explorer the dominant browser, and the company would lose a lot of face if IE were relegated to a very large footnote in Internet history. Without having a default presence on every Dell (NASDAQ:DELL), Lenovo, and Hewlett-Packard (NYSE:HPQ) computer sold, IE would be dealt a huge blow in its efforts to rebuild its Online Business department -- this after numerous successes that included signing up Yahoo! (NASDAQ:YHOO) as a partner.

What's your browser of choice? Did the security of your personal data factor into that choice at all? More to the point, do Microsoft’s Internet Explorer market-share woes affect how you think about Microsoft as an investment? Spill the beans in the comments box below.

Fool contributor Anders Bylund owns shares in Google, but he holds no other position in any of the companies discussed here. Microsoft is a Motley Fool Inside Value recommendation. Google is a Motley Fool Rule Breakers pick. Apple is a Motley Fool Stock Advisor recommendation. Motley Fool Options has recommended a diagonal call position on Microsoft. Try any of our Foolish newsletters today, free for 30 days. You can check out Anders' holdings and a concise bio if you like, and The Motley Fool is investors writing for investors.