I read this as the project is on a network drive while you
are working on it rather than you are generating the output from
you hard disk to a network drive.
I don't recall seeing this particular issue but the forum is
littered with problems caused by working on a project that is on a
network. Try moving the project onto your office hard disk.
Personally if I am working at home, I just zip it all up onto a
memory stick, copy that to my home disk to work and then reverse
the process.
The other possibility might be has the file been copied to
the network as read only?
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