Sudden French keyboard

Using LibreOffice Writer 3.4.1 under Windows 7:

While working on a document, the keyboard will suddenly switch to a French
keyboard configuration. The only option we have been able to find to switch back
to English is to shut down all LibreOffice windows and close all documents.

This has been marked solved in the forum:

However, we’ve tried that, and it doesn’t work in our case. Whenever we have
looked at it, it always shows “US English” even though the keyboard is operating
in French in LibreOffice Writer. (Other programs do not appear to be affected.)

That forum post refers to, not LibreOffice.

My first suggestion would to upgrade to LibreOffice 3.5, then try to reproduce step by step the same issue, and report back here. Even if it is a bug in 3.4.1, it won’t be fixed in that version, but rather in future versions (once reproduced+confirmed it in the latest version).

What OS are you using? Are you sure the system keyboard shortcut for changing keyboards is not being used for something in LiOf, or being typed by accident? I would try disabling the keyboard shortcut and trying then to reproduce the problem.