Windows RT was too expensive for OEMs, and Microsoft's decision to sell Surface RT direct, and lattely through selected retailers - John Lewis and Harrods in the UK - had limited sales and caused confusion for consumers.

"We expect Microsoft to rethink its pricing strategy for RT in the coming weeks. Dropping the price by 60 per cent should get OEMs back onside," said Coulling.

But the fact RT was not compatible with legacy applications left punters reliant on Microsoft's app store which was another reason it failed to get off the ground, Canalys said.

Microsoft is heading for a big fall with the Surface Pro if it follows the same sales strategy, the analyst warned.

Unsurprisingly, Apple continued to lead global pad shipments but grew slower (48.7 per cent) than the market average leaving it with a market share of 49.5 per cent, compared to 58.1 per cent a year ago.

Korean giant Samsung pushed up unit sales to 7.6m from 2.3m in Q4 2011 to take second spot. Coulling said it started to price products more aggressively and took share. Amazon, Google and Lenovo filled the third, fourth and fifth spots.