Oracle Database Discussions

I hope that anybody here can help me with this.
When I'm trying to open the database, I got this error message:
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SQL> SQL> Connected.
SQL> ALTER DATABASE open
*
ERROR at line 1:
ORA-16014: log 1 sequence# 10484 not archived, no available destinations
ORA-00312: online log 1 thread 1:
'C:\ORACLE\PRODUCT\10.2.0\MBOSSTES\REDO01.LOG'


Disconnected from Oracle Database 10g Enterprise Edition Release 10.2.0.1.0 - Production
With the Partitioning, OLAP and Data Mining options
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Any tips what I can do, to resolve this?

Thanks in advanced,
Micke.