Get your whole team working in one database.

Nearly every multi-user problem I get brought in on has the same root: one .accdb file on a network drive, opened directly by everyone. It works with two careful users. Then the team grows, and the symptoms arrive. Records lock for no visible reason, changes vanish, and the file corrupts on the day someone's laptop drops off the Wi-Fi mid-save. None of that is Access misbehaving. It's a single-file setup being asked to do a job it was never configured for.

The fix is the split. Tables and data move into a back-end file that stays on the shared drive; everything else, the forms, queries, reports, and code, becomes a front-end file, and each user runs their own local copy of it. Only data crosses the network after that. The difference is immediate: fewer collisions, faster forms, and updates you can roll out by replacing front-end copies instead of kicking everyone out of the database. I usually add a small version check so an outdated front-end refuses to run, which permanently ends the "half the office is on the old version" problem.

Locking then gets configured deliberately instead of by default. For most teams that means record-level locking on edited records, so two people can work in the same table without silently overwriting the same row, and the second editor is told who has the record rather than shown a cryptic error. Individual logins with scoped permissions come next: the warehouse sees stock, accounts sees invoices, and only the people who should delete records can.

The conversion itself doesn't need downtime. Splitting happens on a copy while your team keeps using the current file; the front-end gets built and tested against real data; and the switch is a single evening: last person out of the old file, back-end goes live on the share, front-end copies land on each desktop. A small launcher script that pulls the latest front-end version at startup means nobody ever has to manually update anything again. The next morning the team opens what looks like the same database, minus the problems.

Set up this way, an Access system serves somewhere around fifteen to twenty-five active users comfortably, depending on how write-heavy the work is. Past that point, or with remote offices in the mix, the same front-ends can be re-pointed at a SQL Server back-end without your team relearning anything. I'll tell you honestly which side of that line your team is on.