Web Advisor language is influenced by one or all of the below factors
1. Your PC language
2. Purchase location of your McAfee subscription
Both of these were in English -- Must be other factor involved...
Please try the below steps and see if it helps
1. Uninstall WebAdvisor from Installed Programs
2. Open Internet Explorer and visit www.siteadvisor.com
3. Install WebAdvisor from there and see if it makes a change