Tips to open THM file

Can't open the THM file? You are not the only one. Thousands of users face similar problems every day. Below you will find tips on how to open THM files as well as a list of programs that support THM files.

THM file extension

File Name Thumbnail Image Format
File Category Raster Image Files

The THM file is supported on 2 operating systems. Depending on your operating system, you may need different software to handle the THM files. Below is a summary of the number of programs that support and open the THM file on each system platform.

Operating systems
  • 3
  • 1
  • 0
  • 0
  • 0
  • 0

What is THM file?

The .THM file is an image file. It contains raster graphics. The file contains a thumbnail, which is a small image containing a preview of the larger image. Typically, thumbnails are the size of an icon. Files in this format are often used by digital cameras, camcorders, and other high-quality image capture devices to enable faster viewing of images. They can also be found in online albums, which speeds up page loading. The file can be opened in the viewing program.

How to open THM file?

The most common problem when using Thumbnail Image Format is that a specific THM is not associated with the program. This is manifested by the fact that THM files open in unusual applications or do not have an assigned program. This can be quickly resolved by following the instructions below.

The first thing you should do is just "doubleclick" on the THM file icon you want to open. If the operating system has an appropriate application to support it and there is also an association between the file and the program, the file should be opened.

Step 1. Install Apple Preview

An often overlooked issue is to make sure that Apple Preview is installed on the computer. The easiest method is to use the system search engine by entering the program name Apple Preview in it. If it is not, installation may solve the problem, as most applications create file associations during installation. Below you will find a list of applications that support THM files.

Step 2. Create association of Apple Preview with THM files

If, despite the installed application, the THM file does not start in the Apple Preview application, you must create a file association. The association can be created using the drop-down list available by right-clicking on the file and selecting Properties. Information about the file and the program that the file is associated with are available here. Using the "Change" button we can select the desired program. If there is no software on the list, simply select "Browse" and manually select the directory where the application is installed. Checking the "Always use the selected program ..." box will permanently associate the THM file with the Apple Preview program.

Step 3. Update Apple Preview to the latest version

If, despite the association of the Apple Preview program with the Thumbnail Image Format file, the file still does not open, check the program version and possibly update it to the newest version.

Step 4. Check for the following problems with the THM file

If the above steps do not help, you can assume that the file itself is not correct. File problems can be divided into the following:

The affected file may be 0 KB or smaller than expected. This suggests truncating the THM file contents when downloading or copying. The only repair option is to download the file again.
The computer may have fallen victim to a computer virus or hacker. A quick virus scan using an up-to-date antivirus program should clear up any doubts. If this is not possible, you can use the online scanner. The scan should cover the entire computer, not only the THM file that we want to open. However, remember that not every infected THM file can be recovered, so it is important to take care of regular backups.
This can happen especially when the program is dynamically developed and the structure of the THM files changes over time. Help should be sought from the software developer, as they usually recommend using free file converters or installing an older version of the program.
The file may be corrupted in a number of ways. The repair method must be adapted to the type of file and damage. Sometimes the program itself has options to repair the most popular THM file corruption.
When reading, a message appears that the file was encrypted or corrupted. The encrypted THM files cannot be played on other computers than the one on which they were encrypted, they must be decrypted before using on another device.
The operating system protects files in some locations (e.g. the root of the system partition) against unauthorized access. These directories are write-protected to them and it's very hard to fix this problem. Copying the THM file to another location will fix the problem.
This can happen on a file that does not support multiple access. In this case, the THM file is blocked by the first application to open it. Running programs (including those in the background) should be verified. If the error persists after closing other programs, wait for a while. Some anti-virus or backup software may occupy the THM file for a certain period of time. If this does not work either, restart the device.