Errors after Upgrading from 3.0.35 > 3.041 I ran the updater from the Admin (local install.) 
After a few minutes, the update failed.

Now when I try to load the site:

Warning: require(C:\Users\rickn\Documents\Craft\Projects\Untye/vendor/craftcms/cms/bootstrap/web.php): failed to open stream: No such file or directory in C:\Users\rickn\Documents\Craft\Projects\Untye\wwwroot\index.php on line 20

Fatal error: require(): Failed opening required 'C:\Users\rickn\Documents\Craft\Projects\Untye/vendor/craftcms/cms/bootstrap/web.php' (include_path='.;C:\php\pear') in C:\Users\rickn\Documents\Craft\Projects\Untye\wwwroot\index.php on line 20


There is no "vendor/craftcms/cms" folder

Is there a way to manually update an existing install? I don't see that option in v3 update instructions.
The easiest way is to make sure you have Composer installed.

Then you can go to your project's root and run composer update to pull in a fresh set of dependencies.