USING 2.40, WINDOWS XP SYSTEM. TRYING TO LOOP SELECT (ALT + B)
SOMTHING LIKE THE BORDER SELECT COMES UP, SO I TRY TO USE THAT TO SELECT A LOOP, IT DOESNT SELECT A LOOP THO AND WHAT EVER PART OF THE OBJECT THAT I DIDNT ENCLOSE IN THE BORDER SELECT , DISSAPPEARS !!!..I STILL HAVENT FOUND A WAY TO MAKE IT COME BACK EITHER… ALSO NO POINTS GET SELECTED AT ALL. DID SOMETHING CHANGE THAT IM NOT AWARE OF ?? IS THERE A NEW KEY ASSIGNMENT FOR LOOP SELECT ?? DOES ANYONE KNOW HOW TO MAKE MY OBJECT COME BACK ??? HELP!!!..THANKX YOU 
Use Ctrl-Z to undo
Loop select changed, use Alt-RightMouseButton
Ring select is Ctrl-Alt-RightMouseButton
Read about all the new and/or changed things in the ReleaseLogs:
http://www.blender.org/cms/Blender_2_40.598.0.html
http://www.blender.org/cms/Releaselogs.34.0.html
Pressing alt+b again also undos what you did. Something in this thread might help:
You shouldn’t write with BIG letters. Cause it’s the same as you shout.