Cannot start MongoDB: System error 1067 in Windows

The error came from an unclean shutdown detected.

Please visit http://dochub.mongodb.org/core/repair for recovery instructions.

a few steps will fix it (as it's written in the link above):

1) remove the file /data/db/mongod.lock

2) run mongod.exe --repair

3) start the mongod service net start MongoDB

For anyone who faced this error on 2020, with version 4.4.1 of mongo, and the accepted answer not solve the issue, here is what I've done:

1. Remove all mongo services from pc (add/remove programs).
2. Go to program files and backup the MongoDB folder.
3. Remove the MongoDB folder.
4. Re-install mongo db.

And it should work.

UPDATE for January 2021, the following saved me without re-installing MongoDB and losing all my data:

C:\Program Files\MongoDB\Server\4.4\bin>mongod --dbpath "C:\Program Files\MongoDB\Server\4.4\data" --repair