Windows release sparks complaints By Richard Waters in San Francisco and Nikki Tait in Brussels Published: May 6 2009 19:49 | Last updated: May 6 2009 23:29 Microsoft has stirred up fresh complaints of anti-competitive behaviour with its release this week of a late-stage trial version of the next Windows PC operating system. The complaints, from some of the leading makers of web browsers, look set to intensify the software company’s regulatory headaches just as it is seeking to head off swingeing anti-trust action from the European Commission over a related issue.