[Solved] Can't boot after upgrading to Mac OS X Lion

[ViniciusPinto]

I upgraded Mac OS X from Snow Leopard to Lion, and now when I try to boot Windows XP as a guest OS, I get the message "FATAL: Could not read from the boot medium! System halted.". I was using VirtualBox 4.1.10, but just updated to 4.1.12 to try to fix it.

Not sure if it matters, but before upgrading Mac OS X, I made the partition a bit smaller.

Any help? Thanks.

PS: There's a lot of threads discussing this error, but since each one deals with a specific context, I decided to post again.

[ViniciusPinto]

Solved: I created a new VM using the existing disk.