VNC copy paste not working between client and VNC session

1. For windows XP run C:\Windows\System32\clipbrd.exe
For Win 7 / 8 where clipbrd.exe is missing, you can download it from here -

2. Make sure vncconfig is not not running.

3. Add vncconfig -nowin -poll=500 & in your xstartup file. For linux your xstartup file will be under ~/.vnc/xstartup

This should work.