Invalid file names

[VicL]

Hi Guys,
I've suddenly got a fault that shows various filenames with opening and closing commas and won't publish. Error message:
One or more invalid images were detected (See log)
WARNING: 'john.jpg' is not a websafe filename
I've check the file names displayed in the selected file name box and they don't show these commas on the actual file.
I have re-loaded the version that I created the site with to no avail.
I have recently installed v 18 but not yet used it. Could this be a problem?
Sorry, couldn't work out how to attach the images
Thanks for any help.
Vic.

[Pablo]

Maybe you have enabled the option 'Check for invalid filenames' in Tools -> Options -> Publish?

[BaconFries]

If you wish to show screenshots then you can either upload the image(s) to your own server and provide a url to it or upload to the likes of the following https://imgbb.com/ and provide the url generated.
I did a quick look at the source code for image naming and could see multiple files starting with numbers and contain brackets ( ) and dashes - Using these could throw errors. Please see the following.

Naming conventions for HTML objects (ID, name, styles)
viewtopic.php?t=64868

How do I name my pages, images and other files?
viewtopic.php?t=131