This is a known issue in PSD 5.0 SP5.5 and PSoC Programmer version 3.06 with Windows Vista. The error occurs only when the Programmer is launched from inside the PSoC Designer. The work around is to launch the PSoC Programmer separately outside PSoC Designer. :
This issue has been fixed and isn't there in versions PSoC Designer 5.0 SP6 and PSoC Programmer version 3.10 and after .