I understand that you are having some issues with your Slingbox SOLO since you are not able to get the remote connection. Instead, you get the W211 error code.
This error code means that your Slingbox SOLO might have lost the Internet Viewing settings for some reason. This means that you need to reset the Slingbox SOLO and run the Setup Assistant for Internet Viewing one more time. If you do not know how to, just check the following links:
I actually determined this issue was due to the MTU settings at the source DSL modem/router. I dropped the MTU down from 1500 to 1300 and my double acks and connection problems went away instantly. This might be the root cause for some people when LAN connectivity works fine but from a WAN location it does not.YMMV
Just as a brief summary, My problem was with web viewing my slingbox from an external location. I would get an error 211 after 20 seconds or so. LAN viewing worked without issue. A packet capture showed malformed packets and double acks which led me to the MTU adjustment.