This is a comment on Requested URL was not found on this server, posted by WikiAdmin at 01.11.2014 09:51

View source for possible error sources

I'll try to reproduce a state where this happens to select the possible error sources.

Looks like the admin panel routine sets / overwrites a related value with en empty / false value in the config table (?)

please check the following values in the config table:

##rewrite_mode##