Why Does It Auto-Replicate?

[Dugantrain]

I have a db in a shared environment. Sometimes, but not always, when multiple users are working in it, the database will replicate. I will see a replica database for every person using it; i.e. if 3 people are using it, then there will be a db1.mdb, db2.mdb, and db3.mdb as well as the original copy. At first I assumed that these were just lock files, but they don't disappear when the user quits; they are entirely new databases. The only thing I can think of is that on my computer, I may have mistakenly changed the "Open With" settings for the ldb file to open with MS Access. If this is the case and is causing the replication, then what Program should I have the ldb files to open with?