You may receive some warnings the first time you open the database on your computer. That is the norm for Access databases that originate on another computer. You can ignore or close these warnings. After the first time through the various warnings, the database should simply load on future attempts to launch it.
You need to enable macros one time to make the database usable. Click OK and enablecontent and that will be the last time you see the warnings.
It is very important that the database be opened by double clicking it from Windows Explorer (9Win7) or File Explorer (Win10), especially if you are running Access 2013 or 2016.
Never save the database in the newer database format. It must remain an mdb file type, not an accdb file type. Saving in the newer format will render the database absolutely useless.