If server terminates during the journal prealloc step then auto recovery is not possible. One is forced to manually run repair to recover from the scenario.

old lock file: B:\rpl2\mongod.lock. probably means unclean shutdown,
but there are no journal files to recover.
this is likely human error or filesystem corruption.
found 3 dbs.
see: http://dochub.mongodb.org/core/repair for more information
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Sun Feb 19 07:51:31 [initandlisten] exception in initAndListen: 12596 old lock file, terminating
Sun Feb 19 07:51:31 dbexit:
Sun Feb 19 07:51:31 [initandlisten] shutdown: going to close listening sockets...
Sun Feb 19 07:51:31 [initandlisten] shutdown: going to flush diaglog...
Sun Feb 19 07:51:31 [initandlisten] shutdown: going to close sockets...
Sun Feb 19 07:51:31 [initandlisten] shutdown: waiting for fs preallocator...
Sun Feb 19 07:51:31 [initandlisten] shutdown: lock for final commit...
Sun Feb 19 07:51:31 [initandlisten] shutdown: final commit...
Sun Feb 19 07:51:31 [initandlisten] shutdown: closing all files...
Sun Feb 19 07:51:31 [initandlisten] closeAllFiles() finished
Sun Feb 19 07:51:31 dbexit: really exiting now