Live crashes during startup after selecting a custom VST folder (Windows)

Ableton Live may crash while scanning plug-ins on Windows if an incorrect VST directory has been selected. Incorrect directories include any folder or path containing non-VST files, such as the root directory of the C:\ drive. For how to choose a correct path, visit Using VST plug-ins on Windows.

VST file type:

VST plug-ins use the file type .dll, which is the same type used by many other files and software drivers on Windows. If you select a folder that contains non-VST .dlls as the Custom Folder for VST devices in Live's Settings → Plug-Ins, this can cause Live to crash. 

To test whether plug-ins scanning is the cause of crashes on launch:

1. Hold down the [ALT] key while launching Live to temporarily deactivate plug-ins scanning. Note that this causes plug-ins in your Sets to be temporarily unavailable, until the next time you start Live normally. 
2. Try opening a Live Set that previously crashed on launch. If you're able to open it successfully while plug-ins are disabled, continue troubleshooting for a plug-in related issue, following the steps below. 

To resolve incorrect custom VST folder:

1. Follow the linked steps to reset Live's preferences.
2. Select a Custom Folder for VST2 plug-ins that does not contain other .dll files.

To correctly install and configure plug-ins on Windows: 

Follow the steps in the guide Using VST plug-ins on Windows. Incorrectly configured plug-ins may cause missing plug-ins, crashing, or other performance issues in Live.