Help! Cannot open Alice World

Last night I was finishing up an Alice 2.0 Class project, but this morning, I can no longer open the program.

Other programs work, just not this, my most important one.

I've tried reinstalling Alice and deleting the .alice file, both no avail.

I installed Alice under C:/Software on my Win XP PC. Until this morning everything worked fine.

Can anyone please help me get this program to open and function again?

Here is the error message I get:

Unable to load world

Alice version: 2.0 04/05/2005
os.name: Windows XP
os.version: 5.1
os.arch: x86
java.vm.name: Java HotSpot(TM) Client VM
java.vm.version: 1.3.1_10-b03
user.dir: C:\Documents and Settings\Steven Shatz\Desktop\Alice\Alice\Required

Throwable that caused the error:

java.io.FileNotFoundException: Not Found: behavior0/elementData.xml

I would like to post the rest of the message, but this website won't accept it, regardless of whether I paste it in or type it. So instead, I will abbreviate:

at ... ZipFileTreeLoader.java:119
at ... Element.java:1438
at ... Element.java:1483
at ... Element.java:1531

Let me know if you need more of this msg to decipher the problem and I will endeavor to provide it.

PS: I don't understand why I not only have this sudden Alice problem, but I am also having a hard time getting postings to this website to work. Could something be wrong with Java on my PC?