How to fix this Permalink Problem

I'm havinga a small but annoying issue regarding permalinks (I'm using multisite+domainmapping).
Basically i have this site
http://www.itervitis-magon.eu
that until today was not using pretty permalinks if I try to activate it my home page gives me 404 and the url becomes like this:
http://itervitis-magon.eu/ui/ti/welcomePage
all the website continue to work as expected though
this is happening only if I visit the main URL
http://www.itervitis-magon.eu

I've granted access already :slight_smile: