Programs/services preventing me from ejecting my external HDD.

I have few programs and services that appear to be preventing me from ejecting my external HDD. These appear in event viewer as event 225. One of them is Windows Defender (msmpeng.exe) preventing disk ejection. Why would WD be preventing ejection of this disk?

Additionally I would like to make my external HDD stay asleep and only wake when I access the disk directly. Currently it is woken whenever I open File Explorer. Is that possible?

I run Macrium Reflect & found I couldn’t eject the backup drive, after much troubleshooting I added the drive to the exclusion list of Defender & found I could then eject the drive.

Bastet said:

I run Macrium Reflect & found I couldn’t eject the backup drive, after much troubleshooting I added the drive to the exclusion list of Defender & found I could then eject the drive.

Interesting. I use my external drive for Macrium backups as well. However this is clean Windows installation and I haven't yet setup backups to the external drive with Macrium. I have been mounting old Macrium images from the drive to restore data but currently there is no image mounted. Do you mean add the drive as a protected folder in Controlled folder access or somewhere else?

I added I:\ (my backup drive) to the allowed list of Defender’s antivirus scanner. I have since removed this entry & removed the drive successfully. I’m still keeping an eye on it but I don’t eject this drive that often.

Bastet said:

I added I:\ (my backup drive) to the allowed list of Defender’s antivirus scanner. I have since removed this entry & removed the drive successfully. I’m still keeping an eye on it but I don’t eject this drive that often.

OK I found the exclusion list for Defender. Now I am left with:

"The application System with process id 4" and

"Program Files (x86)\LightingService\LightingService.exe with process id 3348

stopped the removal or ejection for the device USB

Lighting Service is for Asus Aura software. I have no idea why that would be accessing my USB HDD. I have no idea what System with process id 4 is.

USB Safely Remove (sometimes given away) is very effective at dealing with ejecting disks.
If you search carefully you may find a giveaway. I've used it for years - suggested it to someone on tenforums recently who similarly found it helpful.

dalchina said:

USB Safely Remove (sometimes given away) is very effective at dealing with ejecting disks.
If you search carefully you may find a giveaway. I've used it for years - suggested it to someone on tenforums recently who similarly found it helpful.

This? Safely Remove Hardware better alternative | USB Safely Remove

Yup.. and PID 4:

Information on that here:
system Windows process - What is it?
Is TaskManager running in the tray? If so close/exit it & try ejecting the drive again.

dalchina said:

Yup.. and PID 4:

PID 4 - System/ntoskrnl.exe

Why could this be preventing ejection?

Maybe it's using the external disk for page file or something?