I've upgraded my computer significantly since first installing LFS. Now running WinXP x64 and I'm wondering if it is the cause of my not being able to unlock my LFS install. I've typed in the UN and the GamePW that was sent to me by email, but I everytime I go to hit unlock I get an error saying "Unknown Command".

Only running Windows firewall and no AV is installed just yet. I've even turned off the firewall and still get this error. No router is being used........got a direct connection to the modem. Any suggestions?

Try to do a fresh install of version X, but keep the old LFS install. If it works, you can then copy over the contents of the old LFS install to restore your settings (without the LFS/data/misc folder, though! Delete that one from the old LFS before copying over!)

That did it..........thank you.

Yesterday , I was upgrading procesor (I was have a sempron 3000+ and now I have Athlon 64x2 5200) in my computers, after that I was not reinstall the system . A question is : is that normaly to I lose my settings in LFS , and I was must to unlock S2 again? Because that was happend to me.
And my lfs is now become unstable , he is few time (two or three) a part of us . I think to reinstall the system on the next few days , and then does I must to again unlock s2?

Yes, it's normal that changing the CPU or other significant hardware parts causes LFS to relock, since it uses these parts to identify which computer it was unlocked on (so you can't just unlock LFS and then copy it around to any computer).

The instability could be caused by not reinstalling the whole system, but that's not set in stone. Maybe your PSU is not adequate enough to power the new CPU? Did you overclock it? Did you install new RAM (maybe that is broken)? There's many variables in that equation.

Reinstalling everything could cause your LFS to lock again, that is true. However if you reinstall tomorrow and run out of unlocks, you don't have to wait long, since you get back an unlock every Friday morning.

It seems everithing other are working great , today I was playing COD4 in full details and he was runing without any problems full 3 hours. The hole configuration is working on psu 470 watts . ram is 2 GB on 800mhz dual 128 bits , mainbord is Gigabyte S-series GA-MA69GM-S2H AM2 slot , HDD Western digital 160GB Sata2 3 Gb/s , and Ati X1650 gt 256 ddr3 on 128 bit.
I m same on working on computers, and my kolegs are think to that to :I must the reinstall the system. I see for the wikend that to do.
Tank you for your answer to me . by by