"Does the model exist? Is it beautiful? We’ll never know because the viewer failed to initialize. I’ve checked my .mview paths and my WebGL settings more times than I’ve checked my own pulse. Great tool for local renders, but using the web viewer feels like playing a game of Russian Roulette where five chambers are 'Initialize Error.' Fix the backward compatibility and we’ll talk." The "Tech-Savvy Critique" (Professional) Title: Powerful, Yet Temperamental
Below is a guide to troubleshooting and fixing this error, whether you are a viewer or the content creator. For Viewers: Quick Browser Fixes marmoset viewer could not initialize
The model view file needs to be hosted on a web service with the file being downloadable and public; that should fix the problem. Steam Community Marmoset Viewer could not initialize - CGTrader "Does the model exist