Can't restart a database

Hi there,

I am trying to shutdown and startup an Oracle 10g database thats running on XP Pro.

I connect to oracle via SQLPlus with the following command, "Connect sys as as sysdba". I connect fine.

Then I try to used the shutdown immediate command and i get the following output:
SQL> shutdown immediate
ORA-01109: database not open


Database dismounted.
ORACLE instance shut down.


I then try and run the startup command and i receive the following output:
SQL> startup
ORACLE instance started.

Total System Global Area 373293056 bytes
Fixed Size 789288 bytes
Variable Size 187430104 bytes
Database Buffers 184549376 bytes
Redo Buffers 524288 bytes
Database mounted.
ORA-16038: log 1 sequence# 1039 cannot be archived
ORA-19809: limit exceeded for recovery files
ORA-00312: online log 1 thread 1: 'D:\ACUITY\TABLESPACES\REDO01.LOG'


This has me at a loss. I've tried a few solutions i've found on other sites but I can't resolve this.

Any thoughts?
Thanks in advance.