Solution
When deploying SystemLink Server, the MongoDB database requirement depends on whether you are running the server locally or connecting to a remote database.
If you are installing and running SystemLink Server locally, you do not need to install MongoDB separately. The SystemLink Server installer includes MongoDB and will automatically set it up as part of the installation process.
If you plan to have SystemLink Server connect to a remote MongoDB instance, then MongoDB must be installed and configured manually on the remote host. You must also ensure that a MongoDB account for SystemLink is created before attempting to connect the server to the remote database. Additional instructions can be found in the resource Choosing a MongoDB Deployment.