I agree with Macdrone, mostly*. By formatting it on a Power Mac, you put a newer version of the disk driver on the drive that the SE doesn't understand.

I use Lido or a patched copy of Apple HD SC Setup to format drives like this. Be aware though that the maximum partition size under System 7.5 or earlier is 2 GB.

*The SE doesn't need to have it's drive formatted as MFS as HFS works fine. Perhaps he meant HFS Standard vs. HFS Extended?

c