Restore Oracle 10G Full process record after reloading Windows system

Pre-preparation work:
Back up all the old Oracle files, delete the old directories, and then reinstall Oracle, the directory is the same as the old directory (if not, there are more places to modify).
Install Oracle only, do not create DATABASE, if you have already created a database,
Remove the ==>oracle-oradb10g_home1==>database Configuration Assistant with start ==> All programs.

My database has an instance named Hwdb, and the following is the entire recovery process
Begin

C:/Documents and Settings/gxlineji>oradim-new-sid hwdb
Instance has been created.
C:/Documents and Settings/gxlineji>set oracle_sid=hwdb

C:/Documents and Settings/gxlineji>sqlplus "/as sysdba"

Sql*plus:release 10.2.0.1.0-production on Saturday February 7 22:54:32 2009

Copyright (c) 1982, +, Oracle. All rights reserved.

You are connected to an idle routine.

Sql> Startup
Ora-01078:failure in processing system parameters
LRM-00109:???????????????? ' E:/oracle/product/10.2.0/db_1/database/inithwdb. ORA '

Copy the Inithwdb.ora under the original directory to the hint path Inithwdb.ora. Startup again,

Sql> Startup
Ora-01078:failure in processing system parameters
Ora-01565:error in identifying file ' E:/oracle/product/10.2.0/db_1/dbs/spfilehwdb.ora '
Ora-27041:unable to open File
OSD-04002:????????????
O/s-error: (OS 2)??????????????????????

Replace the existing Spfilehwdb.ora file with the Spfilehwdb.ora in the old directory. and Startup,ok!

Sql> Startup
The ORACLE routine has started.

Total System Global area 314572800 bytes
Fixed Size 1248768 bytes
Variable Size 83886592 bytes
Database buffers 222298112 bytes
Redo buffers 7139328 bytes
Database loading complete.
The database is already open.
Sql> Conn Scott/tiger
is connected.

Now you can connect to ORACLE, but there is a drawback is to set the environment variable ORACLE_SID before each connection, using the DOS command: Set oracle_sid=hwdb
To save this hassle, you must configure the environment variable.

Leave the following as a file with a suffix named Reg (the filename is random), and then double-click to import the information into the registry.

Windows Registry Editor Version 5.00

[Hkey_local_machinesoftwareoracle]
"Oracle_sid" = "hwdb"

To make sure that the ORACLE_SID in the registration table is set correctly, you can search the registry and find all the Oracle_sid,
If a setting is found to be incorrect, modify the value to the correct value ("Oracle_sid" = "SID" to "oracle_sid" = "hwdb").

Re-computer, ok!!