Why won't the vault open?

Question

C++ / C#

Please help me understand, there is the following code from MSDN:

X509Store store = new X509Store(StoreLocation.LocalMachine   );
                store.Open(OpenFlags.OpenExistingOnly);

on 1 computer there are certificates in the store, on another computer this code initially showed certificates, then it stopped, now it returns 0 certificates all the time.
Why 1 and the same code can work, then stop working, I don’t understand in any way.
I tried to change the version of the framework and run it with administrator rights, and that just did not try, that's all. If anyone has experienced something similar, why is this happening?

Answer 1

I remove the question, on another machine the certificate was not in LocalMachine, I mixed up something and confused myself.