Hi Anand,
Well I was not sure that parameter is correct/incorrect and if it is read by the tool or not.
So restart of tool was suggested (I have seen few cases where it was required, not in the same case here) .
Also DIR_PUT is dynamic parameter so system restart is also not necessary.
Generally I change the parameter at R/3 level since its dynamic parameter and also set it in profiles so changes are not lost after the system restart.
I hope it helps.
Best Regards,
Gaurav