This warning message appears when SWBrowser.ldb is present in the Toolbox folder. This file gets created when the user is accessing the Toolbox database or using Toolbox. So when installing or upgrading SolidWorks make sure no one is using Toolbox as SWBrowser.ldb will stop the installation.
Generally, SWBrowser.ldb gets deleted automatically when SolidWorks is closed. If no one is using Toolbox and this ldb file is still present in C:\\SOLIDWORKS Data 202x\lang\english\ then try manually deleting SWBrowser.ldb and the installation/upgrade process will continue without any Toolbox warning message.
