after upgrading to version 6.0.1591 we can't syncronize some clients.
the clients get updates, policies and taks in some cases when we start update on workstation consol.
we checked every thing
firewall is off
ping is ok
we installed netagent many times on it.
there s no spesial event on event viwer/Kaspersky Event Log on the workstation
related ports are open
we checked with klnagchk.exe and we found that everything is ok.
in a case studay we installed win XP on that workstation agane, for 2 days everything was ok but then the problem started again.
even we changed RJ45 cable but it did not solve the problem (foe a possible connectivilty problem).
there are many aother workstations connected to the same switch but they do not have any problem.
there is no spesial software istalled on this workstation.
Please leave a comment if somebody has a similar problem.

How you try to synchronize data? Please try to find clone of problem computers in console (computers with the same name but with "~" symbol and numbers on end of name, for exmple "computer1~123"). Open Find dialog and find using a mask, consisting of computer name with an asterisk ( you need imput "computer1*").