- Thumbs.db files cache thumbnails to speed up image previews in Windows.
- In older versions of Windows, they are generated in each folder, while in Windows 10 and higher the cache is centralized.
- Their presence is harmless, but they can prevent you from deleting folders or saving thumbnails of deleted files.
You may have come across a hidden file called ". Thumbs.db and you've wondered what the hell it is, if it's dangerous or just a nuisance created by the system. Although at first glance it may seem mysterious or even suspicious, thumbs.db files are part of how Windows manages and displays the images stored in each folder.
Today we are going to dive deep into the world of Thumbs.db, so you know how they work, why they appear, if they pose any security or privacy issues, and how you can manage them (deleting them, preventing them from being generated, viewing them, etc.). We'll also review the differences between Windows versions and everything you need to know about these discreet files that accompany your image folders.
What exactly is a thumbs.db file?
The file Thumbs.db It is basically a small database that Windows automatically creates in folders containing images (and also in some with videos or other media files) when you activate the thumbnail view. Its main function is cache generated thumbnails for image files from that folder, so that when you open it again, the previews will load instantly and you won't have to regenerate them every time.
This file is usually hidden by default, so you usually won't see it unless you've turned on the display of hidden files and folders in Windows Explorer. When you browse a folder with many images, Windows generates the thumbnails and saves them inside Thumbs.db, speeding up the user experience and saving time and resources. Their presence is generally harmless and doesn't affect system performance.
Interestingly, this cache system was much more present in versions prior to Windows 10 (especially XP, 7 and 8), since as of Windows 10 the method of storage changed, centralizing thumbnail caches in a specific system folder and stopping creating thumbs.db in each individual folder.
What is the thumbs.db file for?
The utility of thumbs.db files It is mainly to improve the performance and efficiency of Windows when displaying image thumbnails. Prevents Windows from having to analyze the images one by one and generate their thumbnails every time you enter the folderThis way, you can quickly see a preview of each photo without waiting for everything to load again.
This is especially useful in folders that store a large number of images or multimedia filesIf you frequently access these types of folders, you'll notice that the thumbnail display is much smoother thanks to this small database.
Not only local folders can generate thumbs.db: it also appears, for example, when downloading folders via P2P networks, or when browsing network shares, provided that the thumbnail view is enabled.
Is the thumbs.db file dangerous? Does it hide viruses or sensitive information?
A frequent question is whether the files Thumbs.db can be a security or privacy risk. In the vast majority of cases, these files are completely harmlessIts sole purpose is to store thumbnails associated with the images in the folder where they reside, and they do not contain any viruses or malicious elements on their own.
However, there is an interesting nuance related to the privacy. Given the thumbs.db can store thumbnails of images that have already been deleted from the folderIt could be the case that if you once had sensitive photos or files in that folder, their thumbnails are still recorded there. If someone with the knowledge to open and analyze thumbs.db wanted to review them, they could access reduced versions of those images, even though they're no longer physically in the folder. Therefore, if privacy is a concern, it's helpful to know how to clean up or delete these files.
As for viruses, it is not common for thumbs.db to be infected, but like any other file, it could be used by malware to camouflage yourself. To avoid risks, always use a updated antivirus if you detect strange behavior related to hidden files.
Why does it sometimes not let me delete or move a folder with thumbs.db?
Another common problem has to do with the inability to delete or move folders where there is a system-generated thumbs.db file. This is because Windows sometimes keeps the thumbs.db file opened or locked by some process, which prevents you from deleting the folder containing it. The system itself considers the file to be 'in use,' even if you're not currently viewing the folder.
This happens especially in versions like Windows XP, 7 and 8, although it can also happen in newer versions if, for example, you access shared folders on the network from other devices. To resolve this, it is usually enough to close the folder or restart your computer. In more severe cases, thumbnail generation can be temporarily disabled, as we'll see later.
How can I view the contents of thumbs.db?
You may be curious to know what thumbnails are stored in these files, or you may be concerned that they may contain traces of older images and want to review them. Although thumbs.db is not a file that can be easily opened With the usual photo viewer, there are programs and methods to examine its contents.
- FileMagic: Software that allows you to open and view files in various formats, including thumbs.db. Its interface is simple and useful for users without much technical experience.
- Distributions of Linux and the Vinetto program: For Debian-based distributions, Vinetto can be installed with
apt-get install vinetto, and extract thumbnails withvinetto Thumbs.db -o/. This way, you can view the thumbnails stored in thumbs.db in an output folder.
These methods allow you to visually inspect thumbs.db for traces of personal or sensitive images, and take appropriate action if desired.
How to delete thumbs.db and free up space or increase privacy?
If you want to delete these files to free up space, make it easier to delete folders, or protect your privacy, there are several ways to do it depending on the version of Windows.
For versions from Windows XP to Windows 8:
- Open the "File Browser".
- Go to drive C (or another drive where Windows is installed).
- Right click and select “Properties".
- On the “General” tab, click “Free up space".
- In the list, mark “Miniatures” and accept to clear thumbnail caches, including thumbs.db.
There are also specialized programs such as Thumbnail Database Cleaner which can automatically scan and delete all thumbs.db on your system, useful if you have many folders with images.
How to prevent Windows from generating thumbs.db files?
Preventing new thumbs.db files from being created is possible, although you will lose the thumbnail view in folders, as Windows will only display icons or images without previews.
On versions up to Windows 8/8.1:
- Balance Windows key and writes "Folder options".
- Access the tab "View".
- Activate the option "Always show icons, never thumbnails".
In professional environments, you can also use the Group Policy Editor (gpedit.msc):
- Balance Windows + R and writes gpedit.msc.
- Follow the path: User Configuration > Administrative Templates > Windows Components > File Explorer.
- Look for the option "Disable thumbnail caching in hidden thumbs.db files".
- It establishes as “Enabled”, save the changes and restart the computer.
With this, Windows won't generate new thumbs.db files. To re-enable thumbnails, disable it, and the system will automatically create the files when needed.
What happens to thumbs.db files in Windows 10 and 11?
Starting with Windows 10, the system stopped using thumbs.db in each folder; instead, the thumbnail cache information is centralized in:
C:\Users\\AppData\Local\Microsoft\Windows\Explorer
There, you will find files that begin with thumbcacheTo remove all thumbnails, simply delete these files and Windows will regenerate the cache without any traces of old thumbnails.
Advantages and disadvantages of thumbs.db files
Los thumbs.db files offer advantages and disadvantages. Among the and advantages include:
- Improve loading speed of thumbnails, speeding up the browsing of folders with many images.
- They reduce the effort of the system by not having to generate thumbnails repeatedly.
- They facilitate the management of large volumes of multimedia files in different environments.
Los drawbacks include:
- Occasional crashes when deleting or moving folders due to the thumbs.db file being in use.
- Possible privacy risk if they store thumbnails of deleted files and other people access them.
- Constant generation of small hidden files on systems with a lot of multimedia content.
Passionate writer about the world of bytes and technology in general. I love sharing my knowledge through writing, and that's what I'll do on this blog, show you all the most interesting things about gadgets, software, hardware, tech trends, and more. My goal is to help you navigate the digital world in a simple and entertaining way.