Hi, We recently created a new Azure devops artifact feed and published a nuget package. The installation of this nuget package works fine from VS 2017 solution however it doesn't work with VS 2015. When I try to install the package in VS 2015 (via Manager Nuget Packages for solution), it prompts me 3 times to enter credentials before eventually erroring out. I tend to get different errors - Install-Package : Unable to load the service index for source 401 unauthorized - Seems wierd as the same package installation works fine in VS 2017 using same account. user_interaction_required: One of two conditions was encountered: 1. The PromptBehavior.Never flag was passed, but the constraint could not be honored, because user interaction was required. 2. An error occurred during a silent web authentication that prevented the http authentication flow from completing in a short enough time frame. I tried deleing the nuget.config file from C:\Users\<user>\AppData\Roaming\NuGet folder and restarted VS 2015 multiple times without any luck. Appreciate if someone could share the experiences and ways using which this could be resolved. Thanks in advance!

Unable to install custom nuget package in VS 2015 however the same nuget package can be installel successfully in VS 2017

mitesh patel 6

Hi,

We recently created a new Azure devops artifact feed and published a nuget package. The installation of this nuget package works fine from VS 2017 solution however it doesn't work with VS 2015.

When I try to install the package in VS 2015 (via Manager Nuget Packages for solution), it prompts me 3 times to enter credentials before eventually erroring out.

I tend to get different errors -

Install-Package : Unable to load the service index for source
401 unauthorized - Seems wierd as the same package installation works fine in VS 2017 using same account.
user_interaction_required: One of two conditions was encountered: 1. The PromptBehavior.Never flag was passed, but the constraint could not be honored, because user interaction was required. 2. An error occurred during a silent web authentication that prevented the http authentication flow from completing in a short enough time frame.

I tried deleing the nuget.config file from C:\Users\<user>\AppData\Roaming\NuGet folder and restarted VS 2015 multiple times without any luck.

Appreciate if someone could share the experiences and ways using which this could be resolved. Thanks in advance!

Tianyu Sun-MSFT 27,271 Reputation points Microsoft Vendor

2021-12-17T06:45:11.63+00:00

Hi @mitesh patel , does this issue also appear on other NuGet packages, or only on the custom NuGet package? Did you refer to this document: nuget.config file(config section) and try to set the nuget.config file for proxy/server?
mitesh patel 6 Reputation points

2021-12-17T07:47:03.683+00:00

Hi @Tianyu Sun-MSFT , No this happens only with custom NuGet package. I checked the mentioned thread however we are not supposed to use any proxy server as we don't have one.
Tianyu Sun-MSFT 27,271 Reputation points Microsoft Vendor

2021-12-30T07:03:19.34+00:00

Hi @mitesh patel , sorry for delay in reply. If you try to use nuget.exe and run command line like this nuget sources Add -Name "XXXXXX" -Source "URL of your feed" -UserName "XXXXX" -Password "XXXXX", and then open VS and install the customized nuget package, will it work?
mitesh patel 6 Reputation points

2021-12-30T09:03:58.06+00:00

Hi @Tianyu Sun-MSFT , Thanks for your reply! I tried command line as well however still see same issue.
Tianyu Sun-MSFT 27,271 Reputation points Microsoft Vendor

2021-12-31T07:06:44.077+00:00

Hi @mitesh patel , if re-add username and password doesn’t work, perhaps you can check the credentials in Control Panel > User Accounts > Credential Manager > Windows Credentials. Try to remove related credentials of your NuGet package and re-add it, then check in VS again.