The legacy "Lens Blur" effect was replaced by "Camera Lens Blur" in Adobe After Effects CC 2015, causing potential missing effect warnings in older projects. Users should switch to the native Camera Lens Blur or use free alternatives like Fast Bokeh by Rowbyte and Boris FX BCC Lite. For detailed troubleshooting, see the discussion on Adobe Community After Effects 14.2 upgrade removed Lens Blur plugin
Gaussian Blur with Noise/Threshold for highlights lens blur after effects missing free