Hello,
I have the following problem. My Mikrotik router (RB 450, five LAN(RJ45) connectors) doesnt work. I watched the following:
1) When I connect the power cable so I can see that the blue LED light (the green LED doesnt light).
2) Earlier when I connected the powercable so I heard after about 30 seconds "beep" tone. Now I dont hear any tone.
3) When I connect computer (the data cable (RJ45)) so LED (RJ45) doesnt light (I mean both LED computer and Mikrotik).
4) ...but after several minutes I saw that LED on first of five connectors light (about 1 second), then LED on second of five connectors light (about 1 second) and so on. LED on RJ 45 connectors (1-5) ciclically light.

Can you advise me how can I repair my mikrotik?

I am sorry for my terrible english.

connect the serial cable to the computer and mikrotik and use terminal software, se whats its says when it boots. then you can se if the can be a boot error, or maby you can try to reset RB.. if not, maby time to buy a new one

Get the serial cable like Madrox said. Use 115k, 8, n, 1. See where it hangs during boot.

Then before you give up on it, use netinstall to reinstall RouterOS. That will also format the flash and clear the config.

Installing ROS with netinstall is a skill that every Mikrotik owner should learn.

Tom

pleas send me mikrotik schmatic digram my email
najim5672@gmail.com
thanks