I believe the translation for that is "an unexpected error has occurred with the database".
I have just checked your site and it appears to be working.
However, I note from earlier posts that you have had problems with your site and have only just recovered it.
You may want to contact your host for support if there are intermittent failures of that nature.
It's me the admin server, I had to migrate a lot of sites, but this problem of corrupted table is recurring on some sites, even on my old server. I don't know the origin of this problem and the corrupted table are often the same "xf_ip", "xf_search", "xf_post" (frequent on one of my site with xenforo 1.4 RC1), a no reccomanded xenforo version can create a similar bug with the database ?