Okay, here it is:
I was able to view ISPConfig 2 using this URL:
Now, it no longer shows ISPConfig panel. I don't know why. I have checked - the server says the ISPConfig system is now up and running..
I am able to access the folder I have created before in the server...but not accessing the ISPConfig panel..
Any way to troubleshoot?..
Restarted my computer, it still couldn't work. I turned off and switched on again half-an hour later and now it is working again.