It was suggested that I post this here...
I'm trying to install the camera raw update for the Canon Rebel XS in CS4.
I downloaded the newest RAW update, and the files still didn't work, and then when I went back and downloaded the camera-specific update, I get a plugin and photoshop says that "Photoshop does not recognize this type of file."
You should always run the latest version of the Adobe Camera Raw for the particular version of Photoshop you are using.
In your case that means ACR 5.7, which is the last to run with CS4.
There's no such thing as a "camera specific version" of Camera Raw. Once a camera is supported by a specific version of ACR, it will always continue to be supported in all subsequent versions of ACR. You need to run the latest version because each update contains unannounced enhancements and bug fixes.
There will not be any further updates of ACR for CS4, so you must use ACR 5.7.
Note that ACR 6.1 will not work with CS4. The 6.x series of ACR requires CS5.
The error message you describe—"Photoshop does not recognize this type of file"—is returned by Photoshop when you attempt to open the plug-in by double-clicking on it instead of installing it. It is NOT meant to be opened, it's meant to be installed in a specific folder. Read the instructions. As a matter of fact, try updating through the auto updater in the Help menu of Photoshop or Bridge: Help > Updates…
Only if that doesn't work should you perform a manual installation of ACR according to the instructions.
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