The reasons for seeking an alternative include concern over licensing issues, security breaches and the grass-roots power of open-source software.
Some governments in Europe and Latin America, together with the authorities in China, Japan, Singapore, Malaysia and Australia, are encouraging government departments and businesses to replace Microsoft products with a combination of Linux, other open-source products and software from local suppliers.
"Governments and businesses, especially outside the US, are increasingly interested in pursuing strategies that insulate them from Microsoft's growing influence on the IT industry, even if alternate solutions aren't exactly a perfect fit," said Gartner.
Many large businesses outside the US have implemented Linux for similar reasons, the analyst report noted.
In North America, concern about Microsoft's strength is less pronounced, and concentrates instead on enabling Microsoft's rivals to exist in an "ecosystem" dominated by the company.
The most popular alternatives to Microsoft are Linux and other open-source software products such as the Apache Web server. Benefits perceived by users of using open-source software include lower or free initial costs, freedom from supplier lock-in, better security and the potential to help drive local IT economies.
The main difficulty lies in integrating different pieces of open-source software to provide maximum benefit from IT investments.
"Businesses that choose Linux and open-source integration over Microsoft solutions will need new processes in the overall development, deployment, maintenance and support of their IT infrastructures," Gartner wrote.
"A disciplined and carefully considered best-practices process is essential to delivering maximum returns and benefits from Linux and open-source applications. Without it, the investments could lead to higher, unanticipated costs."