Slow Login to domain

our infrastructure is 1 DHCP Doman 50 Desktop and 70 Laptops. From last 3 weeks around 5 more laptop users facing slow login issue. This issue only facing when the Lap shutdown and restart. if login into this computer no problem. but 1st time login to domain ( after shut down )taking too mauch time. after giving login id and password authentication window became idle after 2 mints it will log into domain. only 5 users facing this problem. let me know the solution for this …