Hi @Michael Williams
The maximum upload size setting is configured per web application. To change the maximum upload size in SharePoint 2013, do the following:
Browse to SharePoint 2013 Central Administration site
Navigate to Application Management >>Manage Web Applications
Select your web application and click on Web Application General Settings in the ribbon
In the web application general settings page, you can set the “Maximum Upload Size” value to the value you desire (Say, you want to increase upload size to 500 MB!) and hit OK to save your changes.
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