Vista - very strange problem

this is the second time this happened,


i created a word document on my home computer, which is vista and office 2007
saved it as 97-03 file .doc
onto my 8gb sandisk flash
i edit it on work computer which is xp and office 2007
save
i changed the file name
then i go to open on my home computer again but
the file name is the older name, the document is the older save, and it prompts for document encoding.

and so i think, am i crazy? did i not change the file name? i thought i saved it at work!

so i go back to work here, and open word, and see the document in the recently opened documents list under the file pulldown, and it has the new filename that i changed it to.

so i click on it and it tries to go to the path that i saved it to on my flash drive.


so some how the file reverted automatically back to an older version with the older file name! it freaks me out!