I am facing the same problem. I was using Version 4.0e and kept seeing this error message. I saw that this bug ALF-12061 has been fixed in Version 4.2, therefore decided to try it. However, I find that now (in Version 4.2b) I can only see the site names and no files. In the 4.0e version I could see the sites, files and open them, edit them.
I have not followed the Sharepoint HTTPS instructions, rather I have changed my Mac Office setting to accept basic auth over non-SSL connections.