Remember to create the data and db directories after installing mongoDB else you are going to get an error as seen below.
C:\Users\..>C:\Users\..\Downloads\mongodb-win32-i386-2.2.0\mongodb-w
in32-i386-2.2.0\bin\mongod.exe
C:\Users\..\Downloads\mongodb-win32-i386-2.2.0\mongodb-win32-i386-2.2.0\bi
n\mongod.exe --help for help and startup options
Sat Oct 27 17:39:09
Sat Oct 27 17:39:09 warning: 32-bit servers don't have journaling enabled by def
ault. Please use --journal if you want durability.
Sat Oct 27 17:39:09
Sat Oct 27 17:39:09 [initandlisten] MongoDB starting : pid=8248 port=27017 dbpat
h=\data\db\ 32-bit host=..
Sat Oct 27 17:39:09 [initandlisten]
Sat Oct 27 17:39:09 [initandlisten] ** NOTE: when using MongoDB 32 bit, you are
limited to about 2 gigabytes of data
Sat Oct 27 17:39:09 [initandlisten] ** see http://blog.mongodb.org/post/13
7788967/32-bit-limitations
Sat Oct 27 17:39:09 [initandlisten] ** with --journal, the limit is lower
Sat Oct 27 17:39:09 [initandlisten]
Sat Oct 27 17:39:09 [initandlisten] db version v2.2.0, pdfile version 4.5
Sat Oct 27 17:39:09 [initandlisten] git version: f5e83eae9cfbec7fb7a071321928f00
d1b0c5207
Sat Oct 27 17:39:09 [initandlisten] build info: windows sys.getwindowsversion(ma
jor=6, minor=0, build=6002, platform=2, service_pack='Service Pack 2') BOOST_LIB
_VERSION=1_49
Sat Oct 27 17:39:09 [initandlisten] options: {}
Sat Oct 27 17:39:09 [initandlisten] exception in initAndListen: 10296
*********************************************************************
ERROR: dbpath (\data\db\) does not exist.
Create this directory or give existing directory in --dbpath.
See http://dochub.mongodb.org/core/startingandstoppingmongo
*********************************************************************
, terminating
Sat Oct 27 17:39:09 dbexit:
Sat Oct 27 17:39:09 [initandlisten] shutdown: going to close listening sockets..
.
Sat Oct 27 17:39:09 [initandlisten] shutdown: going to flush diaglog...
Sat Oct 27 17:39:09 [initandlisten] shutdown: going to close sockets...
Sat Oct 27 17:39:09 [initandlisten] shutdown: waiting for fs preallocator...
Sat Oct 27 17:39:09 [initandlisten] shutdown: closing all files...
Sat Oct 27 17:39:09 [initandlisten] closeAllFiles() finished
Sat Oct 27 17:39:09 dbexit: really exiting now
I created data & data\db under c:\ and that resolved the issue.
------
C:\Users\..\Downloads\mongodb-win32-i386-2.2.0\mongodb-win32-i386-2.2.0\bi
n>mongo.exe
MongoDB shell version: 2.2.0
connecting to: test
Welcome to the MongoDB shell.
For interactive help, type "help".
For more comprehensive documentation, see
http://docs.mongodb.org/
Questions? Try the support group
http://groups.google.com/group/mongodb-user
> use test
switched to db test
> db.test.find()
> db.test.save({a:1, b:2, c:3})
> db.test.find()
{ "_id" : ObjectId("508c7765fec0ad937665f28a"), "a" : 1, "b" : 2, "c" : 3 }
> db.test.save({name: 'Upendra'})
> db.test.find()
{ "_id" : ObjectId("508c7765fec0ad937665f28a"), "a" : 1, "b" : 2, "c" : 3 }
{ "_id" : ObjectId("508c79f8fec0ad937665f28b"), "name" : "Upendra" }
>
