QuickLookUIService not responding

KasperFH wrote:

Clear, but it ain't your Mac ;-)

Indeed. All mine work.

Thanks for the help and tips though.

Welcome. At least uninstall F-Secure. Third-party antivirus apps are not needed and are known to cause issues.

Try booting into Safe Mode then Restart normally.

Start up your Mac in safe mode - Apple Support

Install EtreCheck and post the report. Allow Full Disk Access.

https://etrecheck.com/

Use the Additional Text icon to paste in the report.

Besides what others have already said:

Your disk space is running low. Yes, I know you still have some 30+GB free, but that is less than 10% of your system drive, and performance will suffer.

You have stuff from the Snow Leopard era.

This tells us that you have been upgrading system over system, and across different macs, for over a decade, probably.

This accumulates lots of stuff, which may stop to work or cause crashes in newer versions of the OS.

You may not want to hear it, and as you said, it is your mac, but it is also your pain.

If you do a full Time Machine backup and then migrate ONLY the user accounts, you will be able to experience your mac actually working great. Just saying'

KasperFH wrote:

But what's the fix to the problem of the QuickLook not responding?

You have so many third-party apps installed it would basically be hard to pick just one. If that were my Mac, I would erase the whole thing, reinstall the OS and not install so much "stuff".

The most immediate issue…

Major Issues:

Anything that appears on this list needs immediate attention.

Battery failure - Your battery is reporting that it needs to be serviced.

There are plenty of other issues as well.

Running a computer with this amount of Modifications it prone to not work as expected and may result is what this computer is experiencing.

Advise offered is in the best interest of the computer and the experience it may bring to the user.

Two cents from this corner.

EDITED

You're welcome.

++1