Why does a Stand-alone Project MPP file become read-only when saving back to M0SS 2007 document

An MPP file created by Sally in Project 2007 and saved on MOSS 2007 is being checked out and edited by Steve with Project 2003.


When Steve tries to save changes to the file back to MOSS, he is given the error that the file is Read-Only.


We would expect something like “The file was created by a newer version of Microsoft Project and a converter is needed to open it. Do you want to download the converter from the Microsoft Office Website?”


Or:


“Project cannot open this file because the format is not recognized. The file was probably created using a newer version of Project.”


Is the error we are getting (read-only) indicative of a version issue or something else? IF ELSE, where should we be looking?
 
Check the permissions of the directory what the 2007 was stored and then those of the file itself.

MOSS 2007 is being checked out
what software change control are you using?
 
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