Run First As Root?
I've recently run into, apparently, conflicting info about adding new software to a system. At first I read that one should either su to/login as root to run new software for the first time to be certain of having sufficient permissions for the new program to access whatever it needed during its initial setup. That seems to be the wrong thing to do in some cases, as evidenced by my recent attempt to install Firefox and Thunderbird on the Xandros system I'm test driving.
After installing Firefox and Thunderbird on this system exactly as I did on my Slackware system, I got an error message when I tried to run them as user after having run them as root. Neither program gave me any such trouble under Slackware. A search of the LQ forums led me to a solution that involved turning off X authorization (via "xhost -"), running the affected programs as user, and turning X authorization back on (via "xhost +"). The solution worked, and now both programs are playing nice.
Is there a definitive answer as to when a program should be run first as root before it is run as user, or is it trial and error?