Insufficient Priviledge Error When....

Scenario: I'm using an Oracle database (8i) running WIN 2000 to practice with... I log on as Scott/Tiger or Sys/Manager and conn / as sysdba to do different exercises in my Element K Book. Connecting as "sysdba" why would I get insufficient priviledges when I try to use the alter command or shutdown the database? For instance, I got that error when I tried to alter the database to start the archive log mode. Also, got it a second time when I tried to shut down the database as mentioned earlier? What would be the best way to resolve this problem? Thanks in advance.

Because your Windows user account is not in the ORA_DBA group.

Thanks much. That did it!!!

Damn!! You know what?! If we DBA's keep getting problems solved this quickly no one will have to ever open a TAR :D