This package appears to have a custom/proprietary license agreement, and ProGet cannot be automatically determine the license type. You'll need to assign a license type to the URL to allow or block packages with this license.
To install GleamTech.FileUltimate from the command line, run the following command:
nuget install GleamTech.FileUltimate -Version 7.3.0 -Source http://get.gleamtech.com/nuget/default/v3/index.json
To install GleamTech.FileUltimate from the Package Manager Console within Visual Studio, run the following command:
Install-Package GleamTech.FileUltimate -Version 7.3.0 -Source http://get.gleamtech.com/nuget/default/v3/index.json
For projects that support PackageReference, copy this XML node into the project file to reference the package.
<PackageReference Include="GleamTech.FileUltimate" Version="7.3.0" />
FileUltimate is an ASP.NET File Manager and Uploader which supports ASP.NET Core 2.0+, ASP.NET MVC 3+ and ASP.NET WebForms 4+ web applications/web sites. Integrate a file manager into your ASP.NET application or site rapidly. - Browse and manage files with access control. - Accept files with the advanced upload functionality. - Offer a structured and neat download area. - Preview documents (70+ file formats, including PDF © Microsoft Office), images, audios and videos. Note: This package contains a fully working version of the product, however without a license key it will run in trial mode.