By Prince McLean

Published: 03:00 PM EST

Four out of five computers within the workplace are not adequately equipped to make the jump to Microsoft's Vista operating system based on the software maker's stated requirements, one study shows.

A report released last week by desktop management firm Everdream exhibits that 79.9 percent of business machines do not match the recommended requirements for "premium-ready PCs" put forth by the Redmond, Wash.-based software giant. The analysis covered 145,000 desktop and notebook PCs at companies witin its installed base -- especially small to mid-sized businesses -- and highlighted the difficulties many face when upgrading their PCs to the latest Windows OS.

Amongst the largest obstacles to a smooth transition, the report states, are memory and had drive space requirements. Microsoft requires at least 512 MB of RAM to run Vista but recommends a full gigabyte. A mere 30 percent of PCs reportedly met 1GB requirement, according to the report. Similarly, 62.4 percent of the machines did not have the recommended 40GB hard drive storage, including over 18 percent that failed to meet the the required "15GB of free hard drive space" necessary to complete the software install.

"Clearly many companies face stark realities as they consider upgrading their IT assets to Windows Vista in the coming months," said Ed Mueller, chief marketing officer for Everdream. "The costs of getting computers into compliance with Microsoft’s requirements will likely be a huge obstacle to Vista adoption, especially for small and mid-sized companies that have limited IT budget, resources and staff."

Consumers should also be cautious of disparities between labels that appear on some systems," said Mark Minasi, author of numerous books on the Windows operating system. He warns that "a system that is Windows Vista capable doesn't necessarily translate to one that is Windows Vista enjoyable.”

Overall, the data shows that more than 93 percent of companies will face difficulties upgrading at least one their computers to Windows Vista. However, it said just 6.7 percent of machines in its sample would be critically limited by lacking the required processor speed.

Still, Microsoft has already managed to sell some 20 million copies of Vista worldwide since its release on January 30th. Those sales best the 17 million copies of Windows XP sold over its first two months on the market back in 2001. However, comparing the raw figures of the launch sales for the two software releases can be misleading, as the worldwide PC installed base grew significantly in the intervening years.

Based on the growth in the number of in-use PCs over the past 6 years, it could be argued that Vista's sales are off to a slower start than that of XP.