Mongodb service won't start

After running the repair I was able to start the mongod proccessor but as root, which meant that service mongod start would not work. To repair this issue, I needed to make sure that all the files inside the database folder were owned and grouped to mongod. I did this by the following:

1. Check the file permissions inside your database folder
   1. note you need to be in your dbpath folder mine was /var/lib/mongo I went to cd /var/lib
   2. I ran ls -l mongo
2. This showed me that databases were owned by root, which is wrong. I ran the following to fix this: chown -R mongod:mongod mongo. This changed the owner and group of every file in the folder to mongod. (If using the mongodb package, chown -R mongodb:mongodb mongodb)

I hope this helps someone else in the future.

I solved this by executing C:\mongodb\bin\mongod.exe --repair first. Then when I ran MongoDB again by C:\mongodb\bin\mongod.exe, it successfully started.

I solved this by deleting d:\test\mongodb\data\mongod.lock file. When you will reconnect mongo db than this file will auto generate in same folder. it works for me.