You are 100% sure you should have free space on your SharePoint 2013 site, but still getting “Site storage exceeded” error, when trying to upload some new content. Is this situation familiar to you?Let’s analyze what might be the cause of such behavior.
Make sure you have considered two-stage SharePoint 2013 recycle bin origin, as soon as files moved to recycle bin occupy the storage of the site, as if they were present in an ordinary SP library. Since the Recycle Bin in SharePoint 2013 provides two-stage protection against accidental deletions, you should delete files not only from the site’s recycle bin, but site collection’s recycle bin also.
To completely remove a file or an item from SharePoint site, check site collection’s recycle bin under Site Settings -> Site Collection Administration -> Recycle bin and clear up both locations:
– “End user recycle bin items”
– “Deleted from end user Recycle Bin”.
Try to upload new content then.