Front End DB Error - Back End File Path Not Valid

I have recently created a db for a large Printing operation in our company. Previously, the process was all paper-based and extremely inefficient, so obviously this is a huge step in the right direction.

Upon completing the db and providing a demo to the staff, I saved a copy to a shared folder on the network for them to access (.accdb file). We've done this with other dbs before, but with smaller groups (3-4 people). With this db, since there will be anywhere up to 15 people that may want to access it at the same time, the db started crashing during the first phase of pilot testing this week.

I did some more research and found that the db should be split.the users can't open the db anymore.I have a Printing Services shared drive in which created an "Administrator" folder for the back-end (the front-end is in the same location as that folder). When I split the db, I select the back-end location to be within the Administrator folder.

TrackerAdministrator OnlyOS Tracker_be.accdb" is not a valid path. Make sure that the path name is spelled correctly and that you are connected to the server on which the file resides.I know that the file path is valid, b/c I selected it specifically when using the wizard to create it, and I know that the staff have access to the shared drive as they had to open it in order to gain access to the front-end. Plus, it's working for me when I try to open it, just not the others.