Hope this is the right place to put this, but I haven't been able to connect to the Steam server for a day or two now. I keep getting "connection errors." My internet is working fine, and the trouble shooting guide isn't much of a help. Any tips?
Delete the clientinfo.blob file and see if it will work. That file contains a record of your Steam update history, and if it becomes invalid everything will act weird. Deleting it makes Steam re-check your installed updates. That takes a few minutes but fixes many Steam problems.
Beyond that, "connection error" is very vague. Connection to Steam network servers, VAC servers, the game server, the authentication servers, the community server...
I didn't check the filename, "ClientRegistry.blob", in the /Steam/ directory.
Did you confirm your firewall settings or any other filtres that may be active and blocking some Steam traffic? Can you get to the steam sites through a web browser?
Off topic: Thanks to Google's all-seeing-eye, I know I'm the fourth person to make that mistake with the filename. Whee?