Here are some interesting discussions on disabling the Bypass function:
https://bytes.com/topic/access/answe...en-file-access https://bytes.com/topic/access/answe...ive-bypass-key
You can't fully keep anyone out of an Access Database. This is what zmdb is getting at and the above threads address. You just can't with Access alone.
Access was designed to be a Desktop Database, not an Enterprise Database, so it is relying on the same security that other Desktop applications rely on which is pretty much NTFS, a file based security. There are lots of little things you can do to protect your data and your code, but there is no Enterprise solution for an Access database. The most secure it can be is to put the Database on a NTFS Partition on a Server and then restricting the access to the Database based on Windows User Authentication.
If you need more than this, there are lots of options, but my personal favorite is to move the data to SQL Server with Windows Authentication and then publish a .MDE version of the Database for the Users. That way access to the Data is controlled by the Network Admin. But that might be more work than you want to deal with.