Welcome Tommy.
I have not been successful using Access for file attachments. I know SQL can store the Base64 file attachment that InfoPath produces but I do not believe Access can.
Best practice would not be to use Access for a company wide solution anyway. SQL Express is free and is better designed for multi-user use.
If you want to have a real enterprise solution then I would recommend a web/sql server. Check out the Database Accelerator which you can download and install for free. Qdabra Database Accelerator Suite Version 2.0 - Developer
This will give you a whole suite of webservices on your server to interact with Active Directory and your backend database. It allows you to host and store the forms in SQL and gives you granular access control.
If you have questions or would like to see a demo let me know.
I have setup Infopath solutions with Access and even SQL as the backend data repository but it is very difficult and you run into a lot of limitations and frustration. With Database Accelerator, and its web services, you do not have those limitations plus you get lots of additional features and tools which you can leverage. I highly recomend it.