I am trying to install FP8 on OS 10.4.4. Before installing a close all the
applications, but at some point I obtain the message "It appears that a browser
is still running on your system. Please close all browser and click
'Continue'". The trouble is, all the applications are already closed. I even
stopped all the Dashboard processes. If I try again and again, the message
still remains.

Thanks for your help.

OK I found the solution: my OS is in a multi-user mode.