mongorestore error: Don't know what to do with the dump file

in mongodb 3.0 or above, we should specify the database name to restore

mongorestore -d [your_db_name] [your_dump_dir]

You probably saw this error:

ERROR: don't know what to do with file [dump]

Which means in this case, that there is no file or directory called dump in your current working directory. So, Try this first cd c:/hw1-1/ (or whatever the correct syntax is on Windows, I can't test it.) Alternatively you can specify the full path to the dump directory:

mongorestore c:/hw1-1/dump

If you're using mongoexport to create the dump, be sure to use mongoimport rather than mongorestore to load it.