steam.exe (main exception): unable to load library Steam.dll

I had this problem too. In my case it was my firewall blocking Steam. A quick search learned me that the following ports need to be open :

TCP Ports : 27020-27050
UDP Ports : 1200,27000-27015

That's a whole lot more ports than I like to see open, but hey ... at least it works.

*mumble, mutter, grumble*

Originally Posted by berrs001

I had this problem too. If you are using peerguardian check that it is not blocking any of the IP's that valve/steam uses. You can either allow each one individually or disable PG for a short period.

Thanks.. resolved

[Dyer_]

Hi same problem for me.

How can i enable this ports on Vista???Please

[Cyberdave]

I had the same problem and found this thread on google.
Turns out the problem was peer guardian as someone mentioned so thanks!
I put the PG2 window up and watched what happened when I tried to use Steam.
A number of sites including Valve and LimeLightNetworks were being blocked. Just unblocking the ip in PG didnt help so I shut it down and was able to get access.
But yea steam sucks.

[attasbank]

I searched for this problem in google and found this page which helped me in post #15 by Andrewz21
I found out Steam did not install steam.dll so i downloaded the missing .dll file and placed it on C:\Program Files\Steam
And now it works!!!!

If you want to download steam.dll then go to:
http://www.dll-files.com/dllindex/dll-files.shtml?steam

Cheers,

[tiwerd]

Vista Business Edition w/SP1: Unable to Load Library Steam.dll
In my case I was trying to install Steam behind a corporate Proxy. I made sure that I was on a VLAN that was not being (web) filtered by changing my IP to one on a static range that was not filtered. Next I opened IE to an external site that poked a hole in the proxy. I double-checked and found that Vista's firewall was turned on with no effect on Steam. Next I was able to open Steam and it was able to connect to it's servers and get the updated .dll, logged into Steam and entered my license key for F.E.A.R.2 woot!

[Dr@gontunter]

i have same problem firstly than i download steam and install it. it bemoan to me some mistake like steam.dll

Then i downloaded file steam.dll added in steam folder and trying again, then it bemoan some steamUI.dll it lack.

i downloaded and added in steam folder. then i start steam icon and it start updating and again that f*****g "steam.exe (main exception): unable to load library SteamUI.dll"

[antreas9]

windows XP, SP2, but my laptop is the business laptop (so i dont have any access to ports etc).
I tried to install steam, and i got the classic message:
"unable to load library steam.dll"

i downloaded and placed it in the folder of steam, and i got another message:
"unable to load library steamUI.dll, win32"bla bla...
i downloaded and placed it in the folder of steam, and i got the same message.

Do you have any suggestions?

[darklord27]

i have the same problem aswell, even after i connected directly to the port