The default max single file upload size in SharePoint on-premises is 50 MB. In order to increase it, please use the following steps:
SharePoint:
- Go to ‘Start > All Programs > Administrative Tools > SharePoint Central Administration > Application Management’.
- Under SharePoint Web Application Management, click ‘Web application general settings’.
- On the Web Application General Settings page, choose the Appspace SharePoint Intranet web application.
- Under Maximum upload size, type the file size which you want to upload and click on OK. You can specify a maximum file size up to 2,047 megabytes.
IIS:
Repeat the steps listed below for all zones for your web app all the servers which host the web application role.
- Open the web.config from ‘C:InetpubwwwrootwssVirtualDirectories<Virtual Directory>’ folder and increase the following attributes to the desired timeout and size:
<httpRuntime executionTimeout="xxxx" maxRequestLength="yyyy" />
- The timeout is expressed in seconds and the length is expressed in MB.
- Perform an IISReset
This information is extracted from:
https://blogs.technet.microsoft.com/praveenh/2012/11/15/issues-uploading-large-files-to-sharepoint/