Splunk App for Windows Infrastructure: Why am I getting error "Key value store must be enabled. Please enable it" running Splunk 6.2.1?

[spike9090]

I'm getting the following error trying to setup the Windows Infrastructure app
"Key value store must be enabled. Please enable it."

I'm running 6.2.1 64 bit and it's supposed to be enabled by default. I can't find a way to enable it. any suggestions?

[juriggs]

I'm wondering if something strange is happening, because my Windows Infrastructure and Microsoft Exchange app were working just fine until today, when all of a sudden I got this same error:

Key value store must be enabled. Please enable it.

Anybody else experiencing this? I didn't make any configuration changes; things just went wonky on their own.

EDIT

Looks like something wrong with mongoDB. Here's my log file:

old lock file: C:\Program Files\Splunk\var\lib\splunk/kvstore\mongo\mongod.lock. probably means unclean shutdown,
but there are no journal files to recover.
this is likely human error or filesystem corruption.
please make sure that your journal directory is mounted.
found 54 dbs.
see: http://dochub.mongodb.org/core/repair for more information

And from http://docs.mongodb.org/manual/tutorial/recover-data-following-unexpected-shutdown/

If the mongod.lock file in the data directory specified by dbPath, /data/db by default, is not a zero-byte file, then mongod will refuse to start, and you will find a message that contains the following line in your MongoDB log our output:

My file is 1KB, so it's stopping the db from starting. I know NOTHING about mongodb... can anyone help me on how to fix this on a Windows installation?

I should note there was no "unexpected shutdown"... so not sure how this occurred.

EDIT 2

I deleted the mongod.lock file from C:\Program Files\Splunk\var\lib\splunk\kvstore\mongo and restarted my Splunk instance, and now things are working as expected. For those of you who are looking for the mongod.exe file, it's in the bin folder of the Splunk install. I would NOT recommend doing what I did here if you're running a production instance; the only reason I did this is that it's a test instance, and I could care less if I blow the whole thing up. I'd be interested to hear how others fix this, and maybe even here an official response from Splunk, as a rash of this problem seemed to break out this morning...

[0YAoNnmRmKDg]

I deleted the mongod.lock file from C:\Program Files\Splunk\var\lib\splunk\kvstore\mongo and restarted my Splunk instance

worked for me! thanks! splunk 6.2.3 solaris (SmartOS zone)