Overview
When you upload a file to your website, it will be given a name that's the same as the filename. This is often quite an unattractive name, so it's possible for you to change that.
Rename when uploading
When you upload a file it'll put the name in the TITLE box. Edit this and click SELECT
Renaming after it's been uploaded
If you spot an "ugly" file name for a document, you can go back and edit it.
Under the Documents section, hover over the right-hand side of the document block and click the PENCIL icon.
Change the name as required and click UPDATE FILE
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Note: if your file is added to multiple pages, it will update the name on all those pages, saving you time doing it multiple times.