Truecrypt on Win7 Ultimate SP1 x64

[wacher]

I used to use Truecrypt in 32 bits guest hosted on 32 bits host. I crypted the whole virtual system drive without any problem. Some weeks ago I started using 64 bits guest on 64 bits host (both of them are new installation), everything went fine until yesterday. I want to use Truecrypt again, but the pretest failed. Truecrypt bootloader appears, it accepts my password, displays "Booting..." and nothing more happens.
I tried a new guest installation (Win7 Ultimate SP1, no updates, no loader, nothing more just the bare OS) and the situation is the same.
I would appreciate any idea.

[noteirak]

What makes you think this is a Virtualbox issue? What changed between now and before?

[wacher]

I don't know if this is VB issue. But maybe somebody experienced the same already. Maybe somebody can help me
Btw. Truecrypt's manual mention this case and the main tip is: "upgrade your bios or use another motherboard".
The only (main) thing what has been changed is: 32->64 bits upgrade (32bits host/guest -> 64 bits host/guest)

update:
Win7 64bits host + Win7 32bits guest is working like a charm.

[wacher]

Something happend, I tried several times, and now it's ok. I don't know what was the solution.
Please delete this topic if it's possible.