If the Slingbox shows solid lights and you keep getting this specific message, the root cause is the security software running on this specific computer. The following link will provide you with some information that might help you.
If the issue persists, we recommend you to use a second computer in order to set up your Slingbox. You can also try to use the SlingPlayer software as a second option.
Once you fix this issue, we recommend you to check this link. It will provide you with the steps to follow when you use more than one router in your home network.
I just finished connecting my Netgear 300N to my Solo Sling Box. I was having the same problem you are describing. This is what worked for me.
I found the new router did not refresh and replace the old IP address of the sling box. Note: when you replace a router it can only see hardware addresses (IP addresses) that are within it's subnet or its list of addresses it assigns. What happen with me is the old router gave my sling box a 192.168.0.200 ip address. The new Netgear router uses 192.168.1.XXX numbers. So wrong address = can't see you. To get the Netgear router to release and issue a correct address I had to 1. disconnect the network cable to the sling box. 2. Connect to my router via my computer and refresh the list of connected devices so the sling box was gone from the list. 3. Reset the Sling Box Hold the reset button in for about 30 sec. 4. Reconnect the network cable. 5. refresh the connected devices listed on my router. 6. confirm that a correct address had be given my Sling Box 7. Go to slingbox.com and reconfigure my sling box and 8. Happy days are here again. Hope this helps