Starting in Windows 8, the Windows platform supports a maximum of 10 smartcard readers. If more than 10 smartcard readers are available, APIs such as SCardListReaders return a maximum of 10. All other readers are ignored.
Although the Smartcard APIs never enforced a reader limit, some parts of the system were limited to 10 smartcard readers. This sometimes caused sporadic errors when SCard APIs were used over terminal server redirection. There were also some performance issues that occurred in this situation. To resolve these issues, a limit of 10 smart cards was built into the APIs and other parts of the code. This made it consistent with the whole smart card stack.
This article also applies to:
Windows Server 2016
Windows Server 2012 R2
Windows Server 2012
Article ID: 3144446 - Last Review: 21 Mar 2016 - Revision: 1
Windows 10, Windows 10 Version 1511, Windows 8.1, Windows 8.1 Enterprise, Windows 8.1 Pro, Windows 8, Windows 8 Pro, Windows 8 Enterprise