VPN error 734: The PPP Link Control Protocol Was Terminated

I am using Windows Vista Business. When I try to connect to my office
using VPN, I am getting an "Error 734. The PPP Link Control Protocol
Was Terminated." I can connect using VPN with my XP machine.
In the property of the VPN, under "Options" - "PPN Setting",
"Negotiate multi link for single-link connections" is uncheck. Under
"Security", "Require Data encryption (disconnect if none)" is uncheck.
How can I fix this problem ?
Thank you.

Make sure the connection security is set to not use a secured
password, i.e., check "Allow unsecured password" in the dial->properties->
security.

Also make sure you're not "including Windows login domain".