TRY THIS:

ensure the ODBC connection time-out is sufficiently long.

ODBC settings are managed through the system registry and must be configured when Access or any other clients using Jet are closed. The registry settings are available through the Microsoft Windows® Registry Editor (Regedit.exe) under the following key:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Jet\4.0\Engines\ODBC

The default value for this is 60, which means that if it takes longer than 60 seconds to transfer the data from an Access table to SQL Server. Set the value to 0 by double-clicking the name and selecting the Decimal option in the Base options. Change the setting to 0 and click OK.