Office 2007 & 2003 plus Shared Drive = Access denied.

I receive the "Access denied. Contact your administrator" error message after trying to load an excel file saved by Office 2003 but in the new Office 2007 format (via MS compatibility program) from a shared directory.

Here is the deal...

1. Laptop has Office 2003 Pro and is part of a peer to peer network via router with dsl access.
2. Desktop has Office 2007 Pro and has no problem loading or saving files on the Laptop's Shared Directory--via peer to peer network.
3. Desktop saves excel file in 2007 format in Laptop's Shared Directory.
4. Laptop loads and modifies excel file, then saves in 2007 format.
5. Desktop is no longer able to load file..."Access denied. Contact your administrator." is the message from Bill Gates and Company.
6. But...if you copy the files from the Laptop to the Desktop (files now reside on local directory), THEN AND ONLY THEN will Office 2007 load the modified file.
7. Laptop has Windows XP, Desktop has Media Center.

What works?
1. Desktop can load from the Laptop any and all files saved in Office 2007 format...if saved by Office 2007--not by Office 2003.
2. Desktop can load from the Laptop any and all files saved in Office 2003 format.
3. Desktop can load from the Laptop any and all files saved by Office 2007 but formatted for Office 2003.

So...after 4 hours with MS tech support and 5 techs (all from India), I was told, "At this time, MS does not support that particular network feature for Office 2007. Please continue checking with us for a fix, sorry. Is there anything else we can help you with today?"

If the fix is to save all files in Office 2003 format...then why did I buy Office 2007?...So much for forward and backward compatibility!...Glad I bought the Office 2007 at Costco, going back there today to return it and get my $280 refunded! I think I saw a few old Office 2003's still on the shelf.

My $0.02 (USD of course)...I think Office 2007 sucks!