Are there any File or Folder Naming Restrictions?


File and folder naming is something I struggle with continually. European and eastern languages are a particular challenge. Unfortunately, file naming rules are different for each operating system, as well as for HTTP. What works on your machine, might not work as a URL.

So I do my best.

Whatever you upload or add remotely to the File List’s folder will be automatically renamed (sanitized) as follows:


Dots are not allowed in the file or folder name and will be replaced with dashes or underscores. will become date_name.txt

Folder.A will become Folder-A


Spaces are bad trouble in URLs, so:

My picture of my dog.jpg will become My-picture-of-my-dog.jpg

Spaces can be preserved for display. Go to File List > Settings Tab > Display Settings and check the “Preserve Spaces” box. The file name will still have dashes in place of spaces, but they are replaced-back with spaces only for the display.

You can also hide the extension, if that part scares your users…

My picture of my dog

Special Characters

These special characters are OK. Anything else could be troublesome.

$ - _ . + ! * ' ( ) ,

Cyrillic Characters

If the file name sanitizing function has too much trouble cleaning your file name, it may simply be named unnamed-file.ext. You can rename this to something more suitable in the Admin File List.

Use the Description Field

If the file name sanitation is problematic for you, you can use the File Description field to enter the correct name. This field appear immediately below the file name and holds text that is not filtered as much as the file name must be.


Sadly, the rules for naming our files and folder are much more restrictive on the Internet than they are for our personal computers. I try to do my best to make links work while respecting the source name, and I will continue to do so.

Feedback appreciated…

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