SONAR X3 has introduced support for some major new enhancements in regards to VST integration. VST3 support is now fully integrated, as well as background scanning that detects newly added plug-ins while you work. 

If you are upgrading from an older version of SONAR, however, to take advantage of some of these new enhancements you should perform a full re-scan of your VST plug-ins. This is recommended since upgrading from an older version of SONAR to a newer version does not forcefully reset all of your VST plug-in settings.

***
Please note:

The reason we do not forcefully run this process for upgrade installations is because performing this process will remove custom configuration settings applied to plug-ins. For example, if you configure an audio effect as a synth, this setting will be erased and you will need to reapply the setting. Please keep this in mind when performing the below steps.
***

The new VST Scanner is backwards compatible with older versions of SONAR, so performing this rescan will still allow you to run SONAR X2 for example.

To perform a full VST Rescan, you will need to take the following steps:

• Launch SONAR and then go to Edit > Preferences
• Navigate to File - VST Settings
• Underneath Scan Options, place a check mark next to "Rescan Failed Plug-ins" and "Rescan Existing Plug-ins"
• Click the [Reset...] button
• You will be presented with the message: "This will reset configuration settings for all your VST plug-ins to defaults. VST Plug-ins will be unavailable until a VST Scan is performed. Any custom configuration settings will be lost. Are you sure you want to do this?".
• Click [Yes]
• Click the [Scan] button
• At this point, the background VST scanner will scan through your list of plug-ins.
• When the background scanner is complete, you can reapply and custom settings to your plug-ins

IMPORTANT: After going through this process, you will want to remove the check marks next to "Rescan Failed Plug-ins" and "Rescan Existing Plug-ins", especially if you have "Automatic Background Scan" enabled. Leaving all of these options configured simultaneously could lead to a continuous scan loop.

More information on VST Scan settings can be found by clicking here.