Best way to cure Windows network file sharing problem: reboot network Router?

I wasn't fustrated by the Windows network file sharing suddenly not working after I robooted my Netbook. It wasn't the problem of the firewall (ZoneAlarm) or anything, and no matter what I tried the problem still exist. This morning, however, things suddenly get back to normal, and I suspected that it's mainly because I rebooted network router. Otherwise I didn't do anything particularly. Maybe I'll keep this in mind next time I have the same problem.