MikroTik

I am Using Mikrotik RouterOS 2.9.45v and Winbox as the interface. Mikrotik is the DHCP server and i also used it as a bandwidth manager.
For sometimes now i have been experiencing a situation where by some desktop systems or laptops will aquire ip address from the mikrotik but can not browse while other system on the same network will be browsing. But this same system that does not browse on mikrotik will broswe on another network (another internet connection). which give away room for suspecting the LAN , IE and Virus.
Pls i need urgent help as regards this

Try upgrading to one of the 3.x versions, i use 3.11 and it works great.

3.x isnt going to help here. there is something else wrong. what happens when you traceroute out from the machine thats not working ? where does it stop ? what happens when you turn off all your queues that you setup ?

Well on the system or laptop that is not browsing and which aquire dhcp ip from the Mikrotik, I try pingging the DNS and the Mikrotik server ip it will time out. On the queue in winbox, while i try to launch IE on the said systems it will push little packect but at the end page cannot be displayed. I have tried like disable and enable all didnt work. I am a beginer in Mikrotik. Pls i need help

Do a traceroute to your dns servers.
You will find out where the routing stops.
Likely you forgot a default gateway somewhere.

I have had the same problem on a RB1000 running v3.10, 3.11, 3.12, 3.13.
I have switched to a Linux dhcp server for now until i can find the issue. The machines that cannot browse cannot even ping the gateway (Mikrotik) but strangely enough after rebooting the pc a few times or renewing the IP a few times it just starts working - but then its onto the next person with the problem. ie: My mornings were filled with helping people get online.

I have not yet tried v3.14rc as the DHCP server so maybe the problem has been fixed since then. I also have a straight forward setup the RB1000 is my traffic shaper, firewall and DHCP server. (Problem is not my firewall either as i disable all the rules and it still does not work) and the clients all are either Windows XP/Vista or OSx.