I frequently have Excel files, Word documents, and some other files (not only Office files) that are located on a network folder (NAS, active directory managed) open when I shut my laptop, either to walk into another office or meeting room, or even to go home for the night. These are files that are used only by me (at least while I am creating them), but are on a network location for organizational purposes.
Often, when I open the laptop again (in the other room, or the next morning), even though my laptop never was open and not on the network, I am unable to save the files on the network; depending on the file type, I'm either told the file was set to Read-Only because the network name was no longer valid, or some sort of "Network Error Occurred" type message. I have to save-as a different name, at which point I can then delete the old file.
Further, I don't recall having this sort of problem at my previous workplace (which had a similar, though not identical, network - also a NAS managed by Active Directory). I occasionally had problems with one of my programs, but never with Office-type files.
I realize that one fix is to be careful to save all documents and close out before ever shutting the laptop, but that's often impractical. Is there a reason this is happening that I have some control over? Or is this simply the network authentication timing out and there's nothing to be done, other than to be more careful about saving and closing before closing the laptop? Why can't I overwrite the file when using 'Save As', given I have the ability to delete or change the file?