Word 2007 opens documents slow on network drives

[M O J O]

Hi,

If I open a word doc from a network drive, it takes about 1 minute to open.

If I copy the document to my local pc (which takes a second or two),
then Word opens it in less than 4 seconds.

How com that word takes such a long time to open a document on a network
drive? Copying documents between the same network drive an my local pc
is lighting fast, so what's up with Word?

Thanks!!

M O J O