Multiple terminals downloading simultaneously to a Microsoft Access Database with the OMNI Server can experience problems. You may see records dropped, and the Omni Server may log the following error in the log file:

Number 80004005 [Microsoft][ODBC Microsoft Access Driver] Could not update; currently locked by user 'admin' on machine 'MACHINENAME'. [Microsoft OLE DB Provider for ODBC Drivers]

This is a known problem with Microsoft Access databases in a multi-user environment where more than one process is attempting to update the database at the same time. The issue appears to be due to the way Access performs Page and Record locking. This Microsoft Knowledge Base article discusses the locking modes.

There are several ways to address this problem.

1) Microsoft recommends using the OLE-DB Jet provider instead of the ODBC provider to connect to the database. In ITScriptNet, using the direct Access download method uses the OLE-DB Jet driver. Also, you can use the Connection String editor to manually create a connection using the OLE-DB Jet driver in ODBC mode. This Microsoft Knowledge Base Article discusses using the Jet provider.

Be sure to use the OLE-DB for Jet provider, not the OLE-DB for ODBC driver.

2) Use Record Level Locking instead of Page Level Locking. This is an option in the OLE-DB Jet driver, and appears to default to Record Level locking in the current Jet driver versions.

3) Use the Isolate Connections option in ITScriptNet version 2.1 or higher. This option serializes the updates to the database so that only one terminal is actually updating at a time.

ITScriptNet version 2.1 and higher also will detect a failed database update and automatically retry, up to 10 times.