I'm guessing your win7 is the 32 bit variant which just will not boot from a drive greater tha 2tb with a uefi bios motherbd. Win7-64 can boot from 3tb as long as it GPT format if that helps, and win7-32 can also witha drive-overlay program like seagates diskwizard but that only works with non-uefi bios motherbds.
I'm using the Updated 64 bit version of win7 with ie9. And when I used the disk wizard it crashes after about a minute into it. And I already partitioned it to GPT, I'm still having no luck.