US officials are looking at a complaint about Microsoft's upcoming Vista OS regarding its boot-up features, as well as several other concerns, according to court documents filed on Wednesday.

Vista concerns

The main complaint centres on the ability of PC makers to customise a user's experience on their first boot-up with the new OS, in particular a new interface called the 'Welcome Center' that offers users various setup options and commercial offers, the documents say. The documents were submitted on Wednesday as part of ongoing efforts to ensure Microsoft complies with the final judgements of a US antitrust case against it, contained in a court order from May 2003.

Several other concerns have been raised by industry members regarding aspects of Windows Vista, but officials handling the compliance issues have not yet reached any conclusion as to the merits of those complaints, according to the documents.

While source-code worries ease

Meanwhile, a further Microsoft decision to provide licensees with substantially increased access to the source code for its software products, as well as additional assistance aimed at making it easier for their software to be used with Microsoft products, has helped ease US concerns raised last month, according to the filings.

The company told US and European Union officials it was willing to licence its Windows server source code at no additional cost to members of the Microsoft Communications Protocol Program (MCPP) licensing program. This would give them access to relevant source code as well as added assistance through online and in-person training in the use of the source code, Microsoft said in the court filing.

The company's decision to expand its assistance to licensees came in part from concerns filed by US officials in January, according to the documents. In the January 23 filing, officials said Microsoft needed to significantly expand the resources devoted to responding to issues generated by a technical committee as quickly as possible.

"Microsoft's plan - to make Windows server source code available to licensees to assist their development efforts, and to offer licensees both training and technical support - is responsive to plaintiffs' concerns," the officials claimed.