Troubled handset maker HTC has been “shut out” of the next version of Microsoft’s Windows platform, Bloomberg reported, citing “people with knowledge of the matter.”

Apparently, Microsoft has not made HTC one of its preferred partners for the launch of Windows 8 “on concern that HTC doesn’t sell enough devices or have ample experience making tablets.”

It said that both HTC and Microsoft had reiterated their joint commitments in separate statements, without citing any specifics related to future plans.

If true, the move is significant due to HTC’s long-standing partnership with Microsoft – it originally built its business offering operator-branded Windows Mobile devices, before moving into own-brand terminals.

The company was also a launch partner for Microsoft’s Windows Phone 7 smartphone platform.

However, in recent years, HTC’s focus has instead been on terminals powered by Google’s Android platform.

Bloomberg said that Microsoft is looking to tightly control the initial release of devices powered by a version of Windows 8 written for devices using ARM-based processors, such as tablets.

While HTC has previously offered some Android tablets, the company has not generated significant traction in this market – leading Microsoft to focus on other partners.

It was also suggested that HTC wanted to build a device which would feature its own user interface customisation, rather than offering a “vanilla” Windows user experience.

The news comes as HTC cut its own sales guidance for the second quarter, due to lower sales in Europe and delays to its US product releases following a patent dispute.

While HTC announced its One range at the GSMA Mobile World Congress in February, designed to bolster its position in the high-tier, in the meantime the limelight has been stolen by Samsung’s new flagship Galaxy S III handset.

Bloomberg also said that HTC is facing component shortages from suppliers such as Qualcomm, as bigger rivals such as Apple and Samsung exert a stronger influence over the supply chain.