I didn't know what it was. I thought it had been created when I installed Lion DP4 on a separate partition, like the recovery partition..anyway, I went to delete Lion and it's partitions and I deleted EFI with it, only now realizing my stupid mistake. I found an article on how to make a new one, but it's from 2006 and the numbers he's citing don't match up with my system. Here's the article: http://www.ehmac.ca/anything-mac/43204-restore-efi-partition-proper-bootcamp-operation.html He says my boot HD should start at block 409640 but it starts at 409636. Small difference. But then he refers to the bootHD as rdisk0 and mine is rdisk1. Is this normal? I'm really more of a GUI guy, but I can follow instructions. If someone knows how to do this, please....HELP ME!!!! thx.