From my remote workstation, I was able to connect to all my databases until this morning. Suddenly, my TOAD or SQLPLUS is not connecting. I am able to TNSPING my database, but when I open SQLPLUS, it is just hanging there, without any response.

Code:
C:\Documents and Settings>sqlplus user_sbo/pwd_KEEL@sbo1_dev2

SQL*Plus: Release 11.1.0.6.0 - Production on Wed Feb 18 11:28:52 2009

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Same problem with my TOAD. I have verified that my tnsnames and sqlnet.ora files have not been modified. Where do I start looking ?

Thanks.