Develop Reference

How to delete pfx certificate using .net core

I have created code to delete pfx certificate is given below,
X509Store store = new X509Store(
StoreName.Root, StoreLocation.LocalMachine
);
store.Open(OpenFlags.ReadOnly);
X509Certificate2Collection collection =
(X509Certificate2Collection)store.Certificates;
X509Certificate2Collection fcollection =
(X509Certificate2Collection)collection.Find(
X509FindType.FindBySubjectName,
"CN=AWS IoT Certificate", false
);
foreach (X509Certificate2 x509 in fcollection)
{
byte[] rawdata = x509.RawData;
Console.WriteLine(
"Friendly Name: {0}{1}",
x509.FriendlyName, Environment.NewLine
);
Console.WriteLine(
"Simple Name: {0}{1}",
x509.GetNameInfo(X509NameType.SimpleName, true),
Environment.NewLine
);
store.Remove(x509);
Console.WriteLine(
"X509Certificate2 for localhost removed."
);
}
store.Close();
But in the fcollection variable, didn't get certificate collection with subject name.
Here =>
X509Certificate2Collection fcollection =
(X509Certificate2Collection)collection.Find(
X509FindType.FindBySubjectName,
"CN=AWS IoT Certificate", false
);
How to get certificate collection. collection count getting zero.

X509FindType.FindBySubjectName expects a subject name without RDN attribute: "CN=AWS IoT Certificate" -> "AWS IoT Certificate". And make sure if certificate is indeed in the store.
In addition:
store.Open(OpenFlags.ReadOnly)
you are opening store in read-only mode. You can't modify the store using this flag.

Azure Functions keep returning 'The credentials supplied to the package were not recognized'

I have an Azure Functions that keep returning me "The credentials supplied to the package were not recognized". The certificate (pfx format) has been uploaded to Azure as a private key certificate - look at the picture below - and has the status healthy and I can read the 3 certificates in them.
I have also set the appSettings WEBSITE_LOAD_USER_PROFILE=1 and WEBSITE_LOAD_CERTIFICATES=thumbprints but with no luck. Here are my application settings for the function app.
Here is the code I'm using when handling the certificate. I'm following the official documentation by Microsoft - https://learn.microsoft.com/da-dk/azure/app-service/configure-ssl-certificate-in-code#load-certificate-in-windows-apps
using System;
using System.Linq;
using System.Security.Cryptography.X509Certificates;
string certThumbprint = "certThumbprint";
bool validOnly = false;
using (X509Store certStore = new X509Store(StoreName.My, StoreLocation.CurrentUser))
{
certStore.Open(OpenFlags.ReadOnly);
X509Certificate2Collection certCollection = certStore.Certificates.Find(
X509FindType.FindByThumbprint,
// Replace below with your certificate's thumbprint
certThumbprint,
validOnly);
// Get the first cert with the thumbprint
X509Certificate2 cert = certCollection.OfType<X509Certificate>().FirstOrDefault();
if (cert is null)
throw new Exception($"Certificate with thumbprint {certThumbprint} was not found");
// Use certificate
Console.WriteLine(cert.FriendlyName);
}

Summarize the comments provided by author for other communities reference:
The problem was caused by the line of code: X509Certificate2 cert = certCollection.OfType<X509Certificate>().FirstOrDefault();
Changed the line of code to: if (certCollection.Count > 0) { return certCollection[0]; }, then it works.

Certificate found although deleted

I imported a certificate called S0021679776.pfx to a Windows 8 through CERTMGR.MSC.
Then I deleted it (from the certificates manager as well as deleting the file itself).
However, when I run the following code, it still finds the certificate.
Why is that? I searched for certificate by "Issue By" and it is not found.
static void FindCert(string CertificateName)
{
X509Certificate2Collection certificates;
Console.WriteLine("looking for certificate " + CertificateName);
X509Store store = new X509Store("My", StoreLocation.LocalMachine);
store.Open(OpenFlags.ReadOnly);
//FindBySubjectDistinguishedName
certificates = store.Certificates.Find(X509FindType.FindBySubjectName, CertificateName, false);
Console.WriteLine("# of certificates: " + certificates.Count.ToString());
foreach (X509Certificate2 item in certificates)
{
Console.WriteLine(item.GetName());
}
}
}
The output:
looking for certificate S0021679776
# of certificates: 1
C=DE, O=SAP Trust Community, OU=SAP Service Marketplace, CN=S0021679776

Find certificate location on box/server

I am trying to find where the certificate is stored on my local machine and then as well as our dev servers. I can go Run -> MMC -> File - > Add/Remove SnapIns and select certificates and Current User and see my personal certificates. However, I am trying to utilize this code for an HttpWebRequest and I cannot find the url.
string certPath = #"e:\mycertificate.cer"; //This Value
X509Certificate myCert = X509Certificate.CreateFromCertFile(certPath);
request.ClientCertificates.Add(myCert);
In another area we set up a proxy and do it like this.
proxy.ClientCredentials.ClientCertificate.SetCertificate(StoreLocation.LocalMachine, StoreName.My, X509FindType.FindBySubjectName, CertificateName);
So obviously a little different implementation and I am unsure as to where/how to find the location to fill in for the first example.
Solution that worked for me
public WebRequest GetWebRequest(string address)
{
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(address);
X509Certificate myCert = null;
X509Store store = new X509Store("My");
store.Open(OpenFlags.ReadOnly);
foreach (X509Certificate2 mCert in store.Certificates)
{
if (mCert.FriendlyName.Contains("certname"))
{
myCert = mCert;
}
}
if (myCert != null) { request.ClientCertificates.Add(myCert); }
return request;
}

Assuming like you want to pick a certificate somehow and not really care if it is from file or not. In this case you can use certificate store object and find one you need (i.e. by thumbprint). Check out this Get list of certificates from the certificate store in C# and MSDN article on X509Store.Certificates which contains sample too:
X509Store store = new X509Store("My");
store.Open(OpenFlags.ReadOnly);
foreach (X509Certificate2 mCert in store.Certificates){
//TODO's
}

How to retrieve all certificates in your X509Store

I am using the following code to retrieve all certificates in my PC from an asp.net webapp. The certificates collection is empty, and I can't understand why.
I tried impersonating my own user account and I didn't succeed as well. What am I doing wrong?
var store = new X509Store(StoreLocation.CurrentUser); //StoreLocation.LocalMachine fails too
var certificates = store.Certificates;
foreach (var certificate in certificates)
{
var friendlyName = certificate.FriendlyName;
Console.WriteLine(friendlyName);
}
//original problem: fetch a single certificate by its subject name
X509Certificate2 clientCertificate = CertificateUtility.GetCertificate(StoreName.My, StoreLocation.CurrentUser, "CN=mypc.domainname"); //returns null :(

Add this line of code to the second line and see how it works:
store.Open(OpenFlags.ReadOnly);
and then this at the bottom :):
store.Close();

All in one ...
I have an apache server (xamp) with https. I access through https and c# (vs2010)
to a PHP upload page
Install the certificate from i.e in the personal folder certificate, for example.
To view the certicates run "certmgr.msc" , at least in win7
Listing the personal certificates
var store = new X509Store(StoreLocation.CurrentUser);
store.Open(OpenFlags.ReadOnly);
var certificates = store.Certificates;
foreach (var certificate in certificates)
{
var friendlyName = certificate.FriendlyName;
var xname = certificate.GetName(); //obsolete
Console.WriteLine(friendlyName);
}
store.Close();
Find specific certificate
string certificateName = "CN=localhost"; //name found in the var xname
X509Store storex = new X509Store(StoreName.My, StoreLocation.CurrentUser);
storex.Open(OpenFlags.ReadOnly);
X509Certificate2Collection certificatesx =
storex.Certificates.Find(X509FindType.FindBySubjectName,
certificateName,
true);
X509Certificate certificatex = certificates[0];
storex.Close();

I can find certificates by ...
var certificateStore = new X509Store(StoreName.TrustedPeople, StoreLocation.LocalMachine);
certificateStore.Open(OpenFlags.ReadOnly | OpenFlags.OpenExistingOnly);
var certificateCollection = certificateStore.Certificates.Find(X509FindType.FindBySubjectName, "mycert.me.com",false);
certificateStore.Close();
var certificate = certificateCollection[0];
certificateCollection will have the certificates I care about ... if it is just one then I get first element in the collection.

Look in your certificate store(mmc/add/certificate snap-in/my user account/Certificates - Current User/Personal/Certificates) to see the subject name to make sure "CN=mypc.domainname" is whats actually on the cert.
"CN=mypc.domainname"
vs
"CN = mypc.domainname"
...etc