I have a Windows application, which contains a feature where users can upload files (usually scanned documents or PDF file from a USB thumb drive), and the data along with the filename is stored in a database. This file is subsequently uploaded to a central (Windows) server.
However, it has happened recently, where as user has uploaded a file containing a question mark in its name. This has caused problems with the server part as, of course, filenames can't contain question marks.
I haven't got access to the user themselves to ask them what they did, but I can't understand how they could have saved the file in the first place containing a question mark. Our application doesn't allow the user to specify the filename when uploading to its database, it just takes what's stored in the Windows file system.
My guess is that they scanned the document using an operating system other than Windows which does allow question marks and copied from there onto the USB drive or their scanner allows locally stored documents and that allows them. Would this be possible? And if so could Windows still see the question mark in the name when they came to using our application? If the former, what are examples of common OS's that do allow them?