ADS-Scanner detects and displays hidden data streams attached to a main file. NTFS-formatted partitions support files made up of multiple streams: A main or carrier stream and additional attached streams, undetectable through Windows Explorer. So even if the size of your file is appears to be 0 MB, the actual file can still occupy large amounts of disk space. If your Windows reports its running low on disk space, this can be due to alternate data streams hogging your disk space. Here's how to find them.
1. Select „ADS-Scanner“ feature
Launch Ashampoo WinOptimizer and select "File tools" (1). Then, select"ADS scanner" (2).
2. Select drive and run scan
Next, select the drive to be scanned for hidden streams (1) and click "OK" to proceed (2).
In this example, the scan revealed several hidden streams (1). Enable the "Hide common" filter setting to display unknown streams only (2).
"document.txt" appears to include a hidden stream, i.e. "secret_stream.txt", that occupies 145 MB. (1)
Windows Explorer only displays the file size of the carrier stream, i.e. 0 KB. The attached alternate data stream is completely hidden from view.
4. Delete alternate data stream
Select the results of the scan (1) and click "Delete streams" to delete the hidden streams (2).
Click "Yes" to confirm your action (1). The hidden streams, in this case "secret_stream.txt", will be deleted and their disk space reclaimed. The carrier stream, in this case "document.txt", will stay fully intact.
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