We’ve gotten reports of an Office update adversely impacting existing applications that uses Access database to store data and is shared on a network location. Because of the update, people no longer can connect to same Access database file. With the update, only one can use the shared Access database at a time. Microsoft has acknowledged the problem and has a fix in place, but you may need to apply it manually:

Error in Access when opening a database on a network share

If your application is using SQL Server database, you are not impacted by this. However, if your application use Access databases to store data and that database is shared with other users using a shared folder, you will be impacted by this update. Refer to linked article at end of the message for checking whether you are running an impacted build. The impacted versions are listed below.

Microsoft 365 Apps:
Current Channel Version 2111, build 14701.20248
Monthly Enterprise Channel Version 2110, build 14527.20340
Monthly Enterprise Channel Version 2109, build 14430.20380
Semi-Annual Enterprise Channel (Preview) Version 2108, build 14326.20692
Semi-Annual Enterprise Channel Version 2102, build 13801.21086
Semi-Annual Enterprise Channel Version 2008, build 13127.21842

If you are running an older or a perpetual version of Office, you may need to check the Windows update for KB:

KB 5002104 for Office 2013
KB 5002099 for Office 2016
Office 2019 Version 1808, build 10381.20020
Office LTSC 2021 Version 2108, build 14332.20204