FindByThumbprint - certificate exists but not found

Question

I am trying to add a certificate to a web request to connect to Azure services.

My code looks like this:

string certThumbprint = "‎‎thumbprint";
X509Store certStore = new X509Store(StoreName.My, StoreLocation.CurrentUser);
X509Certificate2Collection certCollection = certStore.Certificates.Find(
     X509FindType.FindByThumbprint, certThumbprint, false);

Now I can confirm that the certificate does exist and the thumbprint is correct. However certCollection comes back empty.

Any ideas?

Update: here is how I open the cert store

certStore.Open(OpenFlags.ReadOnly);

FYI I can find the certificate by using FindBySubjectName but I would prefer to use FindByThumbprint — andrewb, Sep 02 '13 at 06:43
I have seen this failed if the certificate is not valid. Check and verify if certificate is valid. You can create a console app just to try this. — Chandermani, Sep 02 '13 at 06:46
@sharptooth I was actually looking for X509Store.Open method (http://msdn.microsoft.com/en-us/library/system.security.cryptography.x509certificates.x509store.open.aspx) in the code above. Not sure if `OpenFlags` might have an impact on finding the certificates. — Gaurav Mantri, Sep 02 '13 at 12:31
@GauravMantri: I didn't notice call to `Open()` was missing. — sharptooth, Sep 02 '13 at 12:36
@sharptooth Yeah. That could very well be the reason for not finding the certificate though andrew-buchan was able to find the certificate by name. Just a thought. — Gaurav Mantri, Sep 02 '13 at 12:38

score 17 · Accepted Answer · answered Sep 02 '13 at 17:49

17

You probably have a hidden character or two at the very beginning of your thumbprint. I've made this mistake many times before when copying the thumbprint from the certificate manager in MMC. Here is a link for more information on this issue. http://support.microsoft.com/kb/2023835

answered Sep 02 '13 at 17:49

Rick Rainey

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What a pain, character is invisible in VS2013 also!! – James Aug 10 '14 at 16:47
I faced this issue, when you paste the Thumbprint in Skype chat box, you can see the hidden character at the end. – Vijai Oct 30 '17 at 15:35

score 2 · Answer 2 · answered Nov 10 '21 at 23:00

2

A safe way to get the certificate thumbprints of the Personal Certificates store is to use an elevated instance of PowerShell.

PS C:\> dir cert:LocalMachine\My | select Thumbprint, FriendlyName, Subject

answered Nov 10 '21 at 23:00

Peter P

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score 0 · Answer 3 · answered Sep 19 '18 at 09:50

I encountered the same issue today, while it's possible that there are hidden characters before and after the thumbprint it's also possible that if your debugging runs under a different user, the StoreLocation.CurrentUser isn't the same Store as the one you open in Windows.

I had this issue running in Service Fabric on localhost

FindByThumbprint - certificate exists but not found

3 Answers3