Is there a large transaction rolling back? Try this query: select s.username, s.sid, t.addr, t.status, t.used_ublk, decode(bitand(t.flag,128),0,'NO','YES') rolling_back from v$session s, v$transaction t where s.taddr=t.addr; ________________________________ From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Richard J. Goulet 3: Database will not shutdown immediate even after half an hour of waiting. Must use shutdown abort. Privileged/Confidential Information may be contained in this message or attachments hereto. Please advise immediately if you or your employer do not consent to Internet email for messages of this kind. Opinions, conclusions and other information in this message that do not relate to the official business of this company shall be understood as neither given nor endorsed by it.