Steam problems... Missing dll?

So I reinstalled steam due to the fact that I could never join LAN games that my brother hosted. I get this error when I startup:

 'Steam.exe (main exception): Unable to load library Steam.dll'

I've looked up on the problem, and all I could find was some forum post of a guy saying to open your ports. I did, reinstalled again just to be sure, and got the same error.

try the steam installer foumd here

 http://support.steampowered.com/cgi-bin/steampowered.cfg/php/enduser/std_adp.php?p_faqid=261

OK dude if this dosent fix it IDK what will!

1. go to RUN under START

2. type REGEDIT

3.find your steam registration files and delete them!

4. start over from fresh download steam, and dont install the games you have on a DISK your account should recognize that you have the games, so just download and install completely from steam!

HOPE this helps!