ID4175: The issuer of the security token was not recognized...

This error is thrown by sts.
Obviously, it is error in  this section:

<issuerNameRegistry type="Microsoft.IdentityModel.Tokens.ConfigurationBasedIssuerNameRegistry, Microsoft.IdentityModel, Version=3.5.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35">
<trustedIssuers>
  <add name="CN = test" thumbprint="12 34 56 78 89 45 45 45 45 45 44 44 44" />
</trustedIssuers>
</issuerNameRegistry>

At first look thubprint of certificate was OK. But when I open it in hex editor there was some characters that was not visible in text editor. I fix this and everything was OK. :)

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