I think I found a bug with FTR : I activated it ( ACP > Config > Icy Phoenix > Posting and Messages > Completely disable Force Topic Read : no AND ACP > General > FTR > Deactivate FTR ? : no ). Until there I had no problem. Now I went on ACP > General > FTR > Deactivate FTR and I enabled it ( yes ) and after that, my viewforum and viewtopic began blank.
I tried to tick ' no ' in FTR > Deactivate FTR and it fixed the problem. But when I let ' yes ' it still bugging x_x
I don't know if I was really clear ... *o*