Microsoft: The messages just aren't getting through

Microsoft's engineers are still struggling to fix a glitch that has left millions of MSN Instant Messenger users without access to the service - the second time in three weeks it's been hit by technical problems.

On the previous occasion, Microsoft was criticised for failing to inform users how long fixes would take.

As many as 10 million people are unable to access their buddy lists at the moment due to a failed disk controller in one of the servers which hosts the service.

The backup for the controller is also affected, according to reports.

The glitch couldn't come at a worse time for Microsoft as it is heavily promoting the MSN service in an attempt to usurp AOL's service as the web's most used IM offering.

It recently came to light that PC vendors had to display the MSN logo on start up interfaces, even if rival instant messaging software was also bundled with the PC.

Microsoft blamed the previous downtime on on hardware failures although the suspicion remains that Passport - the digital identification software at the heart of .NET - could be behind the problems.