Attempting Package Restore from Proget Feed with AD Auth indicates invalid XML

[mhull_0872]

I am trying to restore packages using "dotnet restore" AND "nuget restore" for a feed that requires authentication (AD auth). I have configured my system so that the username/password are stored in the nuget.config file. Whenever I do a restore I receive the following error:

The content at 'http://my.url.com/nuget/myfeed/FindPackagesById()?id='Package.Name'&semVerLevel=2.0.0' is not valid XML.
   For security reasons DTD is prohibited in this XML document. To enable DTD processing set the DtdProcessing property on XmlReaderSettings to Parse and pass the settings into XmlReader.Create method.
 Retrying 'FindPackagesByIdAsyncCore' for source 'http://my.url.com/nuget/myfeed/FindPackagesById()?id='Package.Name'&semVerLevel=2.0.0

I am concerned by the "not valid XML" message that I receive. I am not sure if I have misconfigured something within Proget or not. Is there some sort of limitation here?

[jjones]

Hi Matthew,

After discussing with our team they think this could be related to Windows Integrated Authentication (if it is enabled) or a configuration issue in your nuget.config file.. Can you try to use fiddler to help pinpoint the issue? Also, have you enabled CEIP in ProGet? That would give us some visibility to you errors.

Thanks,
Jason