ИМХО, не наверное, а точно. см. ссылку http://www.keil.com/support/docs/3277.htm
Version 1 of the Keil ULINK JTAG adapter was not designed for and will not work with the x64 Edition of this operating system.
The Keil ULINK2 JTAG adapter is compatible with the Windows x64 Edition as well as older Windows XP, 2000 and NT 4.0 versions.