Windows 7: Problem with CoD4 MW

Well, a few days ago I bought "CoD 4: MW" by steam, and I'd like to play MP. But I can't because game can't find any servers. When I press "Refresh list" it says "Waiting for response from Master Server" and nothing happens. Does any of u knows how to repair it ??

had problems with this game myself,download (if u haven't already) patch 1.6 and 1.7 and get the game up to date, google gamershell,it worked for me after a few clitches,also make sure to install patches in the main CoD folder,if steam hasnt patched them for you,(check game updates)
you can find CoD4 in = program files-steam-steam apps-common
move the patch in here and install
good luck

Well, I did what u asked me for and... :/
Any other suggestions ??

did you download 1.6 first??,do you have automatic game updates on,and did you try different download location???
maybe try googling steam patches for CoD 4 or check their site

upgrade the game step by step. and search for mp patch

Well, steam already updated game for 1.7.568 version, it is the latest one., However I asked for help people from steam forum and they also don't know what the problem is.

CoD 4, No servers - Steam Users' Forums

search for world severs. i heard there are many online servers are open for online COD 4 gaming!

If memory serves me correctly, by default, MW searches the lan. You have to change the filter to internet before it will work, which is really stupid I know.

It "was" no filter,
1. I'm using Comodo IS.
2. When Comodo IS. was working and I wanted to switch on CoD4-mp antivirus blocked it and computer stopped working.
3. I switched of Comodo IS... CoD4-MP still doesn't work.
4. I change options at windows firewall... CoD4-MP still doesn't work.
5. Punkbuster is updated, game has the latest patch. CoD-MP still doesn't work.
6. Looks like it was no patch, no update on PB, no game fault, no windows firewall.(my pc was “up to date” all the time, during this time.
7. I’ve found out that Comodo IS was the problem, because even if comodos FireWall is switched off it still blocks some files, so I had to mark those files as “my own safety files”.



8. On the other hand ,I added to safety files everything connected to CoD4.
9. Everything was updated, just in case.
10. There is another problem with PB, I'm getting kicked all the time from dedicated serwers. But a lot of ppl have problem with that so it's not a problem to find topic how to repair it.
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I hope it help some other ppl in future,
thank you for help anyway.
omt, It would be great if admin, or mod correct my mistakes in english in steps.