I have my solution setup with Enable Restore Packages, the .nuget folder and all expected contents are present. At the root level of the solution I have a Nuget.config (I couldn't use the config file in the .nuget folder because VS was not loading it) with a custom Artifactory source added and with the default nuget source disabled.
Now if I build from the command line (using msbuild) the packages are restored successfully, and if I build within Visual Studio the packages are also restore successfully. However if I click the restore button from within the Manage NuGet Packages window Nuget only downloads one package and the folder is named 1.1.0.0 which is [obviously] not a valid package and doesn't exist when restoring by either of the automatic methods.
Can someone explain what is going on here?
Edit: As per some of the comments this does not appear to be an issue strictly with NuGet but when combined with Artifactory.
After some more investigation the download of this package is also triggered in two other situations (including using Artifactory 3.0.4:
1). Restore NuGet Packages from within Visual Studio by clicking on the Restore Packages button on the Nuget Package Manager Window
3). Attempt to restore packages without being authenticated on the repo