Microsoft is shutting off access to its Windows Live Messenger instant messaging service for users living in countries embargoed by the US, according to reports.

The countries affected by the ban are Cuba, Syria, Iran, Sudan and North Korea, said a ZDnet.com report.

When trying to log in they will be met with the following error message: " 810003c1: We are unable to sign you into the .NET Messenger Service. Reason: Microsoft has discontinued providing Instant Messenger services in certain countries subject to US sanctions. Details of these sanctions are available from the US Office of Foreign Assets Control."

According to ZDNet, a Microsoft spokesperson has confirmed the move although, as many of the sanctions imposed by the US date back nearly 10 years, it is currently uncertain why Microsoft has decided to follow them now by banning the service.

There was widespread anger among the user community last month when Microsoft's Windows Live and Hotmail services suffered a problem that left users without an inbox.

The problem occurred because of "a network issue that we encountered while doing routine maintenance", according to Microsoft. However, the news led to a flood of complaints from vnunet.com readers who had been unable to access their emails.

Many of them argued that the resolution service provided by Microsoft was substandard, with some saying it took much longer than the alleged two hours before they were back up and running.

Microsoft is not alone in feeling the wrath of its customers after problems with its webmail and IM services. Google's Gmail service was branded GFail by many after a major outage in February.