Redmine

Hello,
I installed 1.2.1 on Windows with redmine RailsInstaller 2.0.0 which contains Ruby 1.9.2.
I have chosen French as default language rake redmine: load_default_data).
When I start redmine and I connect, I'm English. I go into my account and I change the language through French and I get the message error:
Processing AdminController#index (for 10.00.00.0 at 2011-09-29 09:10:26) [GET]
Parameters: {"controller"=>"admin", "action"=>"index"}
Rendering template within layouts/admin
Rendering admin/index
ActionView::TemplateError (incompatible character encodings: UTF-8 and CP850) on line #64 of app/views/layouts/base.rhtml:
61:
62: <div id="content">
63: <%= render_flash_messages >
64: <= yield >
65: <= call_hook :view_layouts_base_content %>
66: <div style="clear:both;"></div>
67: </div>

app/views/layouts/base.rhtml:64:in `concat'
    app/views/layouts/base.rhtml:64:in `_run_rhtml_app47views47layouts47base46rhtml'
    app/views/layouts/admin.rhtml:8:in `_run_rhtml_app47views47layouts47admin46rhtml'
    <internal:prelude>:10:in `synchronize'
    C:/Program Files/railsInstallers/RailsInstaller/Ruby1.9.2/lib/ruby/1.9.1/webrick/httpserver.rb:111:in `service'
    C:/Program Files/railsInstallers/RailsInstaller/Ruby1.9.2/lib/ruby/1.9.1/webrick/httpserver.rb:70:in `run'
    C:/Program Files/railsInstallers/RailsInstaller/Ruby1.9.2/lib/ruby/1.9.1/webrick/server.rb:183:in `block in start_thread'
I need help, thank you in advance