How to recover lost disc space

I successfully set up the EX2Ultra, users, shares and web access.
One of the users was uploading a large video file over the internet and after 1.3G the transfer failed.
In the Usage on the share i see 1.3G being used.
When i try to access the file uploaded, there is nothing. Even when i go in with the web file viewer, there are no files in the share.
How do i release this disc space? Is there something like a recover lost disc space or scan disc?
Thanks for your help


Di you install the Antivirus? I had the same issue and uninstalled the antivirus and got my space back

Thank you for your suggestion. No, I did not use any antivirus software on the Mycloud.