MS isn't my thing, so I hope somebody can give me a pointer.

We have a Windows domain, with a Server-2003-SP1-Enterprise file server. One of the specific files is a MS Excel 2007 (XLSX) file created by user LK. In the "Security" preferences setting, about a half-dozen users (including me) have access to this file.

LK is the owner and has "full control", while the rest of us have "Read" , "Read & Execute", and "Write" permission. LK is also the owner of the directory that this file resides in. I don't know if that's relevant.

So far so good.

My desktop machine has Windows XP SP3 , and Excel 2003 SP3 , and the "Office Compatibility Pack" which lets me read and write the new XLSX files. However, whenever I write the file, the permissions are changed. The newly-written file only has permissions for LK and me, and both are "Full control"

So in short, what am I doing wrong, and how should I set this up to do it right, keeping the permissions on the file that were there when I started?