I do not know why after I changed another computer, all my contact groups are gone, all the contacts are put into the "other contacts"... I do not want to sort it all over again...i have like more than 500 people in my list. But if I open the messenger in my old computer, I can still the groups, like "Classmate", "Teacher"...etc... Is there a way to backup the grouping and reload it back to my new computer? I tried to replace the history but doesnt work at all.
Please help me!!!! Thanks!

If you see your contacts in their own groups when you visit Windows Live Hotmail's Contacts tab, then don't panic. Sign in Messenger, tick this option: Windows Live Messenger Options>Secruity>"This is a shared computer, don't store my address book, personal message and display picture here".Press OK, sign out Messenger, then resign in. Check if your contacts are shown under their own groups now.

If you cannot see them in their own groups in Hotmail, then it means your contact groups info has been removed from servers. I don't think there is much thing to do in this case. Move again your contacts into their groups.