Yeah, when you say "stream", does that mean you downloaded the game, ie torrent? If that's what you did, I can tell you exactly what the problem is and how to fix it.
no i mean Steam, as in Valve Steam :)
I'm familiar with Valve Stream. They are (as far as I know) a legitimate site with licenses to do what they do. Regardless, the issue your facing with secuROM is that this is a SONY implementation that is essentially integrated code that serves error messages if the original disk isn't in the drive. You'd get the same thing if you were using a burned copy. You either need to take this up with VS, or get a legit media copy for yourself.
Verify the game cache and reinstall. See if it resolves the issue. If it is infact a legit copy, this should fix whatever went wrong.
ive just done that, it found 30 files that were downloaded, i tried to run it again and it came up with the loading box then it crashed so then i tired it again but then it just went back the the securom message :/
I would try the Steam Forums for help, as it seems to be more about Steam than about Windows 7. I have installed Steam as well as Batman AC and had no problems at all. But I know that the Steam Forums CAN be helpful (not always, but in the smaller subforums there are less trolls)
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