Microsoft’s latest mistake could cost it $7bn

As mistakes go, this is a pretty catastrophic one. Microsoft has revealed that the Browser Choice System it has to offer in the EU, doesn’t work on millions of PCs. It’s an error that could also end up costing it big time.

The measure, which was forced on it in 2010 by the European Commission, in a bid to make sure that people knew that browsers besides Internet Explorer existed.

In an official release, the Redmond-based tech giant admitted to the problem and said it was working on a fix:

we believed when we filed our most recent compliance report in December 2011 that we were distributing the BCS software to all relevant PCs as required, we learned recently that we’ve missed serving the BCS software to the roughly 28-million PCs running Windows 7 SP1.

The European Commission isn’t exactly what you’d called tickled with the explanation. According to The Next Web, Microsoft learned about the bug on 2 July and started rolling out a fix the next day. The company hopes to have “substantially complete distribution of the BCS software to the PCs we initially missed by the end of the week.”

Even though it’s offered to extend its compliance period an extra 15 months, Microsoft could still face a US$7-billion fine from the EC if it finds it had willingly neglected the order.