I believe the limit is 2GB. Have a look here http://www.databasedev.co.uk/access_specifications.html
. To overcome this I would suggest splitting your database if you haven't already done so?
This means that the tables are stored separately, this is known as the back end (BE). Then all of your queries, forms, modules and macro's etc are stored in what's know as the front end (FE).
Essentially you end up with 2 or more db's. Another advantage of having this setup is if you have many user's using the db over a network for instance, you can locate the BE on a network drive and then distribute the FE to your user's.
This makes it easier to develop and update the FE without affecting the BE. It also means that many user's can commit changes without sacrificing performance.
Have a look here for more info http://www.databasedev.co.uk/split_a_database.html
Hope that helps.