Samba authentication issue

Hi guys we have a running samba server and it works ok, issue came when our windows samba clients were upgraded to win7... some users cant login and some needs to enter their password 7x before they can login.

the net advise to set NTLVMv2 on the win7 security options it works on the users who cant login but to other users they have to enter their password 7x before they can login... is there any other solution to this

Upgrading our samba is however not an option :frowning: we are using version 3