Problem: “I cannot open my jpeg image, yet see its thumbnail. Is there a fix.”

Solution: Go for the following manual method to fix the jpeg error:Use hex editor to extract the thumbnail of corrupt jpeg file
If the previous manual solution is not helpful, then go for the following software solution:

1. Download & install Stellar JPEG Repair on your Windows computer
2. Run the software and use its friendly interface to repair jpeg files
   If you encounter  jpeg error where you can see the thumbnail of a jpeg image but not the complete image, go through the below methods through which you can fix the issue.

Before going for the fix, let us know how jpeg files can get corrupt. A jpeg file contains two parts jpeg-header and jpeg-scan. When there is alternation of bits to any part of the jpeg file, it gets corrupt. At the time of opening the corrupt jpeg file, photo viewing app throws error message.
If your jpeg image file shows thumbnail but not the image, then your jpeg-scan data is damaged and jpeg-header is intact. Thumbnail, which is the miniature version of the same file in lower resolution, is stored in the header part to provide faster preview. You can recover thumbnail information from the jpeg header.

The manual process to recover jpeg thumbnail is as follows:

1. Open the corrupt jpeg file using a hex editor

Note: A hex editor is a binary file editor of the computer program that allows manipulation of the fundamental binary data. With a hex editor, a user can see or edit the raw and exact contents of a file, as opposed to higher-level application software.

2. Open a perfect jpeg file in the same editor
3. Extract the thumbnail data basis the perfect
4. Save the thumbnail photo to your computer

The preceding manual method is appropriate for advanced users. There is an easier method for general users, who can use software to repair jpeg files. One such software is Stellar JPEG Repair, which can handle all intricacies of corrupt jpeg files and performs multiple repair simultaneously.
The steps to use jpeg repair software are as follows:

1. Download, install, and run the software in your computer
2. Click Add file and select the corrupt jpeg file
3. Click the Repair button to start the repairing process
4. Preview the file to check for inconsistency
5. Click the Save button to save the file on the desired location

Well, you have repaired your JPEG image. The software’s powerful repair engine repairs the corrupt jpeg file by adding or rectifying the jpeg header, extracting the thumbnail, fixing invalid jpeg file structure, and other advanced repair solutions.

To Summarize
The blog points out the jpeg error where the thumbnail of a corrupt jpeg file is visible but not the full-sized image. The manual method to fix the issue is to use hex editor to extract jpeg thumbnail information. However, the manual method is for a technically inclined user. The easier and more preferred way  is to use the Stellar JPEG Repair software to repair corrupt jpeg files.