I have left it the same name as the current project I'm working on ( usually something like "EM FINAL_10a.veg" I have changed it to a different name, added BACKUP to the name even tried "Untitled.veg". I also create a folder named "Backup" and save to that as well. Trick is I have done this before with this project and had success. I made some changes in later versions of the project and thought I would backup again and now I get the error message. There is some file in the project I sure causing a conflict I guess but can't figure which.

have you tried "cleaning" your project media? Are all files online?

Guess I need clarification as to what "cleaning" and "online" means?

Cleaning:

Go to TOOLS and press CLEAN PROJECT MEDIA.

Online:

Any media that is in the timeline but not physically available will be shown as "Media Offline".

Got it! Thanks! I'll check...

Still no go...project was clean and no off-line media for sure.....still get the error that the "The file name is not valid"

Just my whacky system I'm guessin'

Just a long shot: could it be that Vegas - or your file system - for some reason does not like the file name of one of the media files? If so maybe take your project, go to about half on the timeline and delete all media "to the end" - then clean project and try to save with media.
If the error is still there then the bad file must be in the first half of your project - and you could then either do the above with the half project or delete a track + clean protect + save with media until you have identified the (possibly) bad file...

Or else it could be an error in your file system - then, in Windows Explorer, one-by-one right-click your disks, go into Properties, Tools and do the Error-checking.

Looking forward to hear what you find...

I believe that one possible cause is destination combined-path/file-name-string length (i.e. overall length of the combined path/file name string -- aka 'fully qualified file name' -- of the project itself and/or any individual file contained in the project).

Windows enforces a maximum number of characters in a path/file name string. Hence, if some file in the project contains a name which is longer than that allowed, Windows will refuse to save the file.

You can try a test with a very short project name in the root directory of a destination drive to see if the save is successful. If it is, you have a starting point to work with and can adjust as needed to achieve a successful save.

Hope this helps,
jerald

When examining path names as problem areas for store and retrieve, please recall the bug that Windows OS creates if you let it default to naming new drive volumes on its own. You must rename any drive so titled so that it works as legitimate call for a path entry.
I know this affects XP, Win7, and I think Win 8?