Unable to find valid certification path to requested target. Install failed

[edudutra7]

NU3012: Package 'Newtonsoft.Json 13.0.3' from 'https://api.nuget.org/v3/index.json': The author primary signature found a chain building issue: PartialChain: unable to find valid certification path to requested target. Install failed

[KUNGERMOoN]

I have a similar problem when installing Microsoft.CodeAnalysis.CSharp package. Here's the end of nuget output:

Acquiring lock for the installation of System.Runtime.CompilerServices. Unsafe 6.0.0 Acquired lock for the installation of System.Runtime.CompilerServices. Unsafe 6.0.0

PackageSignatureVerificationLog:

Packageldentity: System.Numerics. Vectors.4.5.0

Source: https://api.nuget.org/v3/index.json

PackageSignatureValidity: False

PackageSignatureVerificationLog:

Packageldentity: System.Buffers.4.5.1

Source: https://api.nuget.org/v3/index.json

PackageSignatureValidity: False

NU3012: Package 'System.Buffers 4.5.1' from source 'https://api.nuget.org/v3/index.json': The author primary signature found a chain building issue:
PartialChain: unable to find valid certification path to requested target
NU3028: Package 'System.Buffers 4.5.1' from source 'https://api.nuget.org/v3/index.json': The author primary signature's timestamp found a chain building issue: 
PartialChain: unable to find valid certification path to requested target
NU3012: Package 'System.Buffers 4.5.1' from source 'https://api.nuget.org/v3/index.json': The repository countersignature found a chain building issue:
PartialChain: unable to find valid certification path to requested target
NU3028: Package 'System.Buffers 4.5.1' from source 'https://api.nuget.org/v3/index.json': The repository countersignature's timestamp found a chain building issue: PartialChain: unable to find valid certification path to requested target PackageSignatureVerificationLog:

Packageldentity: System.Runtime.CompilerServices.Unsafe.6.0.0 Source: https://api.nuget.org/v3/index.json

PackageSignatureValidity: False

Install failed. Rolling back...

Executing nuget actions took 1.4 sec

[radimitrov]

Unfortunately shortly put this is likely caused by the network class changes from the Xamarin.Android to .NET 6/7/8 Microsoft migration and the root cause will probably never be fixed. I'm working on implementing a workaround.

[radimitrov]

I will continue investigating this issue to work out a fix. Haven't been able to do almost anything the past few days due to a high fever...

[radimitrov]

The issue is fixed now. Next update should be tomorrow.