You finish copying files to an external SSD connected through a USB-C hub.

The progress bar disappears. Nothing seems to be using the drive anymore.

Then you click Safely Remove Hardware, and Windows says:

“This device is currently in use. Close any programs or windows that might be using the device, and then try again.”

Sometimes waiting a few seconds solves it.

Sometimes the warning keeps coming back even though every visible file is closed.

The useful question is not:

“Why won't my USB-C hub eject the drive?”

It is:

“Which Windows process still has an open handle to the drive?”

A drive can appear idle in File Explorer while an application, background service, backup tool, search process, or security scan still has a file or folder open.

The safest solution is to find that process, release it normally, and then eject the drive again.

Start the Lock Hunt With Your Last Action

Before opening advanced tools, think about what happened immediately before the warning appeared.

Did you just:

• copy a large folder;
• edit a document directly on the SSD;
• preview photos or videos;
• unzip an archive;
• run a backup;
• export a project;
• browse folders in File Explorer?

That timing is your first clue.

Try this short reset first:

1. Stop all file transfers.
2. Save files stored on the external drive.
3. Close programs that opened files from the drive.
4. Close File Explorer windows showing that drive.
5. Wait 10–30 seconds.
6. Try Safely Remove Hardware again.

If the drive ejects now, you probably had a temporary open handle rather than a USB-C hardware problem.

If the same warning returns repeatedly, move to the actual lock hunt.

Build a Suspect List

A surprising number of programs can keep an external drive busy.

This is why repeatedly clicking Eject often does not help.

Windows is not waiting for another click.

It is waiting for the application or process to release the storage device.

Find the Process That Is Locking the Drive

When the obvious programs are closed but Windows still refuses to eject the drive, use Microsoft's Sysinternals Process Explorer.

Microsoft's Process Explorer utility can show which handles and files are currently open by running processes.

Suppose your external SSD is:

E:

Open Process Explorer as administrator.

Then use:

Find → Find Handle or DLL

or press:

Ctrl + F

Search for:

E:\

You may find a process such as:

explorer.exe

Photoshop.exe

SearchIndexer.exe

backupsoftware.exe

or another application referencing something on the drive.

Now the vague Windows warning has become useful.

Instead of:

“Device is in use.”

you know:

which process is using it.

Release the Lock Safely

Once you identify the process, avoid immediately forcing the handle closed.

Close the owning application normally whenever possible.

If an Editing App Owns the Handle

Save your project.

Close files stored on the external drive.

Exit the application if necessary.

Then eject again.

If File Explorer Owns It

Close all Explorer windows showing the drive.

If the reference remains, open Task Manager and restart Windows Explorer, then retry.

If Backup or Sync Software Owns It

Check whether:

• a backup is still running;
• file verification is active;
• files are synchronizing;
• the application is scanning changes.

Let the task finish or pause it through the application's normal controls.

If Security Software Owns It

Allow the scan to finish when possible.

On a managed computer, do not permanently disable endpoint protection simply to remove an external SSD.

If the Owner Is System

Do not terminate the Windows System process.

Instead:

wait → stop storage activity → close applications → retry

and restart Windows if the drive still cannot be released safely.

Use Handle for a Command-Line Lock Search

IT users can also use Microsoft's Sysinternals Handle utility.

Microsoft describes Handle as a tool for identifying which programs have a particular file or directory open.

For example:

handle E:\

This can be useful when the same ejection issue appears across multiple managed Windows PCs.

Use the result primarily to identify the process.

Do not force-close handles unless you understand the consequences, because abruptly closing a handle can cause application instability or data loss.

Why “Nothing Is Open” Does Not Always Mean the Drive Is Free

Users often assume:

“I closed the file, so nothing is using the disk.”

But Windows and applications can still hold references to:

• folders;
• thumbnails;
• metadata;
• project files;
• databases;
• recently accessed media.

There is therefore an important difference between:

No file is visibly open

and:

No process has an open handle on the drive.

That is exactly why Process Explorer is more useful than guessing.

Check the Windows Removal Policy

If the problem happens frequently, also check how Windows manages the external drive.

Windows provides two primary removal policies:

Quick removal

and:

Better performance

Microsoft's external-storage removal policy documentation explains that Quick removal reduces write caching, while Better performance enables write caching and makes proper safe removal more important.

To check the setting:

Disk Management → External Disk → Properties → Policies

Quick Removal

Designed to keep external storage ready for removal more easily by minimizing write caching.

Better Performance

Allows Windows to cache write operations for improved performance.

If your drive uses Better performance, a finished File Explorer progress bar does not necessarily mean every pending write operation has completed.

Quick Removal Does Not Mean “Pull It Anytime”

Quick Removal reduces reliance on write caching.

It does not make it safe to disconnect the drive during:

• file copying;
• project export;
• backup;
• database activity;
• synchronization;
• active writes.

If Windows specifically reports:

This device is currently in use

it is still better to find the process or wait for activity to finish instead of ignoring the warning.

Is the USB-C Hub Actually Causing the Problem?

Usually, the “currently in use” message points first to software activity rather than a defective USB-C hub.

The hub becomes more relevant when the drive also:

• disconnects randomly;
• disappears from File Explorer;
• reconnects repeatedly;
• freezes during transfer;
• becomes read-only;
• shows RAW;
• reports 0 bytes.

Those are different failure states.

If an SSD becomes write-protected or behaves as though it is read-only, follow the external SSD read-only troubleshooting guide instead.

If an unexpected disconnect leaves the volume showing RAW or 0 Bytes, stop writing to the disk and use the external drive RAW or 0-byte troubleshooting workflow before formatting or making unnecessary changes.

If the SSD disappears entirely, the problem has moved from ejection locking to detection, power, cable, enclosure, or connection troubleshooting. In that case, use the external SSD not showing up through a USB-C hub guide.

Direct Connection vs. Hub: Use It as a Classification Test

If you still suspect the hub, compare the same drive both ways.

Test A

External Drive → Laptop Direct

Use the drive normally.

Then eject it.

Test B

External Drive → USB-C Hub → Laptop

Repeat the same workflow.

Do not change the application or test files.

Both Connections Refuse to Eject

Focus on:

applications → open handles → Windows services → removal policy

The hub is unlikely to be the main cause.

Direct Connection Ejects Normally, Hub Setup Does Not

Now look for something that changes specifically when the hub is connected.

For example:

• another external drive becomes active;
• backup software automatically starts;
• an SD card is being indexed;
• additional storage volumes appear;
• the SSD also freezes or disconnects.

If the only symptom remains:

Windows says the device is in use

the next step is still to identify the process that owns the handle.

A Cleaner Storage Setup Can Make Diagnosis Easier

Changing hardware does not close a Windows file handle.

So a new USB-C hub should never be presented as a direct fix for:

“This device is currently in use.”

Hardware becomes relevant only when the storage connection itself is also unstable, or when several storage devices need a clearer and more consistent connection path.

For workflows built around multiple USB-C SSDs, a USB-C hub with four dedicated 10Gbps USB-C data ports and up to 100W PD pass-through can keep multiple USB-C storage devices on clearly identified data connections.

The LENTION CE31s is useful here as a storage-connection option, not as a way to release a locked file.

Its four USB-C data ports are rated up to 10Gbps, which makes the configuration more suitable for users connecting USB-C SSDs and other high-speed USB-C peripherals than relying on repeated USB-A adapters.

If Windows still reports that the external drive is in use, however, the open application or process must still be identified first.

For users working with USB-A external drives together with SD or microSD cards, a USB-C hub with three USB 3.0 ports, SD and Micro SD readers, and up to 100W Power Delivery provides a more suitable mixed-storage configuration.

The LENTION CB-C36B combines:

• 3 × USB 3.0 ports up to 5Gbps;
• SD card reader;
• Micro SD card reader;
• up to 100W PD pass-through;
• HDMI up to 4K@30Hz.

That makes it more naturally suited to workflows where users regularly move files between:

external HDD / SSD

SD cards

and:

microSD cards

through one desk connection.

Power Delivery can also help keep the host charging while storage devices and other peripherals are attached.

However, this distinction remains essential:

Neither CE31s nor CB-C36B can release a Windows file handle.

Their role is to provide a cleaner storage connection after the process-level lock has been identified and resolved.

Read the Result, Not Just the Warning

Once you search for the lock, use what you find to determine the next action.

This is safer than repeatedly clicking Eject until you eventually decide to pull the cable.

Quick Answers

Why does Windows say the drive is currently in use when nothing is open?

A background process, service, or application may still have an open file or directory handle associated with the external drive.

How do I find what is preventing my USB drive from ejecting?

Use Process Explorer, press Ctrl + F, and search for the external drive letter or a path on the disk.

Can File Explorer prevent safe removal?

Yes. Explorer can still reference folders, previews, thumbnails, or files on the drive. Closing the relevant windows or restarting Windows Explorer may release the reference.

Does Quick Removal mean I can always unplug the drive?

No. It reduces write caching but does not make it safe to unplug a disk during active reads, writes, backups, or synchronization.

Is the USB-C hub causing the warning?

Usually not directly. The warning primarily means Windows still considers the storage device active. Investigate the USB-C connection when you also see freezes, unexpected disconnects, or detection failures.

Will using another USB-C hub solve “This device is currently in use”?

Not if a Windows process is still holding an open handle. A different hub may improve an unstable physical storage connection, but it cannot close the software-level lock.

Final Takeaway

When Windows says:

“This device is currently in use”

do not start by replacing the USB-C hub.

Start by finding the lock.

Use this sequence:

Stop File Activity

→ Close Visible Apps

→ Search Open Handles

→ Identify the Process

→ Release It Normally

→ Check Removal Policy

→ Eject Safely

Only move into USB-C port, cable, power, enclosure, or hub troubleshooting when the external drive is also showing genuine connection instability.

The key rule is:

If Windows refuses to eject an external drive, first find the process that still owns a handle to it.

That turns a vague Windows warning into a specific process you can identify and safely close.