The agency that governs educational technology in the United Kingdom has advised schools in the country to keep Microsoft's Windows Vista operating system and its Office 2007 software out of the classroom and administrative offices.

"Upgrading existing ICT systems to Microsoft Vista or Office 2007 is not recommended," said the British Educational Communications and Technology Agency, also known as Becta, in a report issued this week.

Becta officials said a study the group commissioned found that upgrading school systems from Windows XP to Vista and Office 2007 would increase costs and create software compatibility problems while providing little benefit.

"Our advice is to be sure there is a strong business case for upgrading to these products as the costs are significant and the benefits remain unclear," said Stephen Lucy, Becta's executive director of strategic technologies, in a statement.

Becta also singled out for criticism Microsoft's failure to support the Open Document Format -- which is recognized by the International Organization for Standardization -- in Office 2007. Instead, the software uses a new Microsoft format called Office Open XML.

"Microsoft should provide native support for the ODF file format increasingly used in competitor products and those that are free to use," Becta said in its report.

The agency said U.K. schools can consider using Vista or Office 2007 software only when they are buying new batches of PCs. Even then, however, they're advised to take a long looked at alternatives based on Linux and other open source products, such as the OpenOffice.org desktop package.

"Schools and colleges should make pupils, teachers and parents aware of the range of free-to-use products (such as office productivity suites) that are available, and how to use them," Becta said.

The report's conclusions could end up costing Microsoft millions of dollars in lost sales in the U.K. public-sector market.

Becta's advisory mirrors similar moves taken by public agencies in the United States. Last year, the Department of Transportation placed a ban on the use of Windows Vista, Office 2007, and Internet Explorer 7 because of cost and compatibility concerns.