MODALplugin will appear in your DAW as an Instrument / Soft Synth plugin. It will not appear in the list of FX plugins, MIDI plugins, or MIDI-controlled FX plugins. Therefore please check you are searching for it in the correct list.
MODALplugin is available as a VST3 (macOS / Windows) or AU (macOS only) plugin only. It is not available as VST2 (sometimes just referred to as VST, which is a different format compared to VST3). For information on why please see here.
Therefore MODALplugin will only appear in host applications that support VST3 or AU plugins. Please refer to your host application’s documentation to find out if it supports these formats.
A support article here should help understand this.
Please note that VST3 support is only available in Ableton Live version 10.1 or higher. Therefore on Windows MODALplugin will only run in Ableton Live version 10.1 or higher.
Also MODALplugin is 64 bit only, and only supported on macOS 10.10 and above or Windows 8 and above.
Therefore MODALplugin will only appear in 64 bit host applications running on supported OS versions.
Windows 7 and older OS are not supported.
On Windows, make sure you are running MODALplugin version 1.4.2 or above. Earlier versions of MODALplugin wouldn't always appear on some Windows computers.
On Windows, also please check your VST3 file location settings in your DAW / host application.
MODALplugin should be installed into the following location (the dedicated VST3 directory) - C:\Program Files\Common Files\VST3. Please check that this is correct.
Some host applications allow you to set / change the plugin folders they use - please check yours is using the above location. Also some hosts (e.g. Ableton Live) require you to explicitly enable the use of this VST3 plugin system folder - please check that this option in the host settings is enabled.
For more information about VST plugin locations on Windows, see here.
If MODALplugin is still not appearing in your DAW after checking all of the above, please email us at firstname.lastname@example.org with the following information - computer OS and version number (e.g. macOS Catalina 10.15.5, Windows 10 Home 64 bit), DAW / host and version number (e.g. Ableton Live 10 Suite 10.1.14), MODALplugin version number (e.g. 1.4.0).