Short answer
Scan All keeps the previous complete results visible until every selected drive finishes. If you cancel the scan or a drive disconnects, the unfinished set does not replace them.
Keep removable drives connected until the scan ends. Run a new scan after adding, removing, or reconnecting a device.
When to use this method
WinDirStat analyzes selected storage trees; Osenpa Disk Analyzer also coordinates fixed and removable volumes under one cancelable Scan All operation.
Before you start
Connect every drive, note each label and capacity and keep portable devices powered through the scan. Scan inventories one drive. Scan All handles the selected drive set as one operation. Its results are staged, which means the old complete set stays visible until the whole new set succeeds.
How we checked this guide How multi-drive scans and disconnect limits were verified.
- What we reviewed
- Reviewed Scan All coordination, staged result commitment, drive fingerprints, removable-device refresh, generation isolation and cancellation in Osenpa Disk Analyzer.
- What we confirmed
- Scan All owns one operation and stages its results until every selected drive completes. Stale callbacks cannot overwrite later work, and cancellation or failure leaves the previous complete tabs intact.
- Important limit
- Two USB drives can both appear as E: at different times. Capacity and volume identity must match before comparing results; a later device needs a fresh scan.
Coordinate volumes without stale results
Identify the connected volumes
Record drive letter, label, capacity and file system before starting so similar removable devices remain distinguishable.
Choose Scan All or one drive
Use the combined operation for a broad snapshot; isolate one device when troubleshooting speed or access.
Hold the hardware state steady
Avoid reconnecting, relabeling or removing media while its inventory is active.
Check whether the set committed
If every selected drive completes, use the new per-drive tabs. If Scan All is canceled or fails, the previous complete tabs remain instead of a half-new set.
Start a fresh generation after changes
Refresh drives and rescan when a device is replaced so old progress cannot describe new media under the same letter.
Volume-state hazards
- Swapping devices that reuse one drive letter
- Assuming a canceled Scan All partly updated the tabs
- Disconnecting during result preparation
- Comparing inventories without volume labels
Checkpoint: Drive checks
- Write down each volume label and capacity.
- Keep devices attached through result preparation.
- Confirm the whole new drive set replaced the previous tabs.
- Refresh and rescan after any hardware change.
Osenpa Disk Analyzer
Stage one Scan All result across fixed and removable drives without mixing old tabs with a partial new set.