I don't know, as that doesn't sound right, as the canon T4i isn't supported in 6.7, but in the 7.1 version of camera raw according to the adobe pages:
You have photoshop cs5 on your laptop (windows 7) and you can open the canon T4i camera raw files in photoshop cs5?
It's actually one of the reasons I posted- Yes, I can open them on CS5 on Windows 7, but not on XP. I read the same knowledge article.
I tried to open one of the camera raw files from this page and photoshop cs5 on windows 7 with camera 6.7 couldn't open it
Do you shoot both raw and jpeg files?
Despite what it says in the ACR vs Camera matrix suggesting T4i support in 7.1, the readme for ACR 7.2 says that it was the first version to handle T4i files and the readme for 7.1 doesn’t mention the T4i. My computes all have ACR 7.3 RC so I can’t verify, easily, now.
Is it a possibility that the Win7 computer is reading DNGs not CR2s from the T4i?
If you are sure you are able to process T4i CR2 files in CS5 ACR 6.7, then please upload one of those files to www.dropbox.com ( or similar large-file storage site ) and post the public download link so we can take a look.