How to uniformly expand the left thumbnail by default across multiple PDFs? Method for batch modifying the open view

When dozens of PDF reports, contracts, or archives need to be delivered, opening each file individually and setting the left thumbnail view consumes a great deal of time and can easily lead to missed changes. With the "Set PDF Initial View" feature in HeSoft Doc Batch Tool , you can add multiple PDFs at once, uniformly set "Show on Open" to "Show Page Thumbnails," and then output the processing results in a batch. This article explains the complete process of file import, option settings, saving, and result checking, using before-and-after effects and the operation interface, and also addresses questions such as reader compatibility and the difference between bookmarks and thumbnails.

Many PDF documents are not read sequentially from the first page to the last. When reviewing a project report, people may want to go directly to the conclusions and appendices; when checking a contract, they may need to jump quickly to the signature page; when browsing a product manual, they often look for diagrams or operation illustrations based on the page layout. If the PDF does not open with the left thumbnail panel expanded by default, users first need to find the sidebar entry in the reader and then switch to page preview mode.

When an enterprise needs to organize a batch of PDF files uniformly, the problem is no longer "how to display thumbnails for one PDF," but "how to make multiple PDFs use the same opening view." Setting each file individually is not only time-consuming but may also miss individual files. HeSoft Doc Batch Tool is an office software designed for batch file processing, and its "Set PDF Initial View" feature can apply the same navigation panel settings to multiple PDFs, reducing the cost of repetitive operations.

The specific goal of this article is to import many PDFs in batches, set their "Open to" option to "Show page thumbnails," and output the processed results. The thumbnails mentioned here are the page previews in the PDF reader sidebar, not the file cover thumbnails in a Windows folder, nor the conversion of each PDF page into JPG, JPEG, or PNG images.

I. Applicable Scenarios: Why Unify the Opening View of PDFs

The initial view determines the navigation method that the reader prioritizes when opening a PDF. For a notice with only one or two pages, whether the thumbnails are expanded may not matter much; for materials with dozens or even hundreds of pages, page previews can help readers first understand the overall structure and then jump directly to the target location.

1. Sending Complete Sets of Project Materials Externally

Consulting reports, audit materials, design proposals, and project delivery documents often contain multiple PDFs. Uniformly setting them to show thumbnails when opened can allow recipients to browse each file in a relatively consistent way, without having to switch the navigation bar again each time a file is opened.

2. Organizing Contracts, Policies, and Archive Files

Contract attachments, rules and regulations, and historical archives usually have many pages, and some scanned PDFs do not have usable table-of-contents bookmarks. Page thumbnails can assist in locating content through page appearance, such as quickly finding pages with tables, seals, signatures, or images.

3. Creating Electronic Manuals and Training Materials

PDFs such as product manuals, course materials, and meeting handouts often contain covers, tables of contents, chapter pages, and graphic pages. Displaying thumbnails immediately after opening can help users quickly determine the distribution of content.

4. Batch Standardizing Historical PDFs

PDFs generated by different people and different software may have inconsistent initial navigation methods. Using a batch office tool to unify the settings can avoid manually opening each file, searching through menus, and saving files separately, and is especially suitable for centralized organization tasks involving a large number of files.

II. Effect Preview: Differences Between Not Displaying Thumbnails by Default and Displaying Them by Default

Before Processing: The Main Text Is Already Open, but the Page Structure Is Not Intuitive

Before processing, the PDF can be read normally, but when opened it mainly displays the main text, and page thumbnails do not appear in the sidebar by default. Readers can see the current page and adjacent page content, but cannot directly preview the page arrangement of the entire document.

As can be seen from the example, the reader has controls such as page number and zoom ratio at the top, but the page thumbnail navigation area is not automatically expanded. When facing a long document, if one wants to find a certain table or attachment page, it often requires continuous scrolling, or first manually opening the reader sidebar.

After Processing: Page Thumbnail Navigation Automatically Expands on the Left

After completing the initial view setting, reopen the output PDF in a compatible reader, and the left side will display preview images of each page with the corresponding page numbers marked. Click any thumbnail to jump to the corresponding page.

The position indicated by the red arrow is the page thumbnail area. The key change after processing is in the reader's side navigation panel, not in the main text content itself. The two effect images are used to show the difference in opening state; the differences in content and page count of the sample documents do not affect the judgment. During actual acceptance, one should compare using one's own original files and output files.

It should be noted that what is saved in the PDF is the initial view preference, and the final interface will also be affected by the reader type and user settings. For example, the sidebar styles of desktop readers, built-in browser viewers, and mobile applications may differ, and not all programs will display it in exactly the same way.

III. Operation Steps: Uniformly Setting Multiple PDFs to Expand Thumbnails by Default

Step 1: Find the Initial View Setting in the PDF Tool

After starting HeSoft Doc Batch Tool , select "PDF Tools" in the left navigation area. Then find "35. Set PDF Initial View" in the function list and enter it.

The description on the function card indicates that it can batch set the navigation panel, page display method, and default zoom ratio when PDF files are opened. This time only the navigation panel is processed, so the subsequent configuration should focus on "Open to" and should not mistakenly select "Delete bookmarks in PDF," "Modify PDF metadata," or format conversion functions.

After entering the function page, four process stages can be seen: select records to process, set processing options, set save location, and start processing. This process is suitable for one-time configuration and multi-file execution, and is also the efficiency advantage of batch file processing compared with modifying files one by one.

Step 2: Add Multiple PDFs at Once

On the "Select records to process" page, use "Add files" or "Import files from folder" at the top to add the content to be processed.

The two import methods are suitable for different situations:

• Add files: suitable for selecting a small number of specified PDFs from different locations.
• Import files from folder: suitable for situations where many PDFs are stored centrally in the same directory, reducing the need for repeated selection operations.

After importing, the software will list the files in a table. The example screenshot shows 4 records, with file names 1.pdf, 2.pdf, 3.pdf, and 4.pdf in order, and also lists the file path, extension, and creation and modification times. At this point, do not rush to the next step; first complete a list check:

1. Check whether the record count at the bottom is consistent with the number of files planned for processing.
2. Confirm that the paths point to the correct business directory, not an old version or backup directory.
3. Confirm that the extension is pdf.
4. If a record should not be processed, use the delete button in that row's operation area to remove it.
5. If the overall import is incorrect, use "Clear" and then select again.

After confirming that there are no errors, click "Next" at the bottom of the page.

Step 3: Set the Open-To Display Method to Page Thumbnails

After entering "Set processing options," three setting areas can be seen: "Open to," "Page display method," and "Default zoom method." First enable "Open to," and then select "Show page thumbnails" below it.

In the screenshot, the "Open to" switch is already enabled, and the radio button before "Show page thumbnails" is also selected. This setting means: make this batch of PDFs request that the reader display page thumbnail navigation when opened.

The same area also provides the options "Do not show sidebar" and "Show bookmarks," and the three have different meanings:

• Selecting "Do not show sidebar" means the PDF will not actively expand the corresponding side navigation area when opened.
• Selecting "Show bookmarks" means the reader will prioritize displaying document bookmark navigation; if the original file has no bookmarks, the navigation value may be limited.
• Selecting "Show page thumbnails" means the reader will display page-by-page preview images, which is suitable for the need described in this tutorial.

If there is no need to unify the page layout or zoom ratio, it is recommended to keep "Page display method" and "Default zoom method" disabled. Modifying only the necessary options can reduce additional impact on the original reading experience. After completing the configuration, click "Next."

Step 4: Select the Save Location for Output Files

The third stage of the process is "Set save location." Specify the output directory according to the on-screen prompts so that the processed PDFs are saved to an identifiable location. For formal materials, it is not recommended to directly replace the only original file during the first test. You can create a separate directory to save the results, and then judge whether the task was completed correctly by file name, quantity, and spot-check results.

If processing materials for multiple departments or multiple projects at once, it is recommended to create separate output folders to avoid mixing PDFs from different batches. The save directory should have normal write permissions and reserve enough space. If the source files are located on a portable hard drive, network directory, or sync drive, confirm the connection is stable first to avoid path failure during processing.

Step 5: Start the Batch Processing Task

After setting the save location, enter the "Start processing" stage. Confirm again that the processing target is "Show page thumbnails," and then start the task according to the on-screen prompts. The software will process the imported PDFs in sequence using the same parameters, without requiring the user to open each document and repeat the settings.

The value of batch processing is not only saving clicks, but also improving setting consistency. As long as the import list and option configuration are correct, files in the same batch will use the same processing rules, reducing common manual errors such as missed changes, wrong selections, or forgetting to save.

Step 6: Reopen the Output PDFs to Verify

After processing is complete, do not rely solely on the task completion prompt as the final acceptance criterion. Open the files in the output directory to check whether the page thumbnails automatically expand on the left. During verification, it is recommended to close previously opened PDF windows to avoid the reader still showing old files or cached states.

If there are only a few files, they can be checked individually; if there are many files, first spot-check samples of different types, such as scanned documents, text reports, PDFs with many pages, and PDFs with bookmarks. For important materials such as contracts, bidding documents, and stamped documents, also check whether the page count, page orientation, main text, and seal display are normal.

IV. Common Questions and Precautions

1. After setting the initial view, will all readers automatically expand thumbnails?

It cannot be simply understood that all readers will behave exactly the same. Standard desktop PDF readers usually read the initial view information in the file, but some browsers, mobile applications, or simplified viewers may ignore this preference, or may prioritize restoring the user's last sidebar state. Therefore, it is best to test using the reader commonly used by the file recipient.

2. Why is the old state still visible after the setting has apparently succeeded?

First confirm that the file being opened is the output file, not the source file with the same name in the original directory. Second, close the original reading window and reopen it. Some readers remember the interface state of a single file when it was last closed, and this behavior may override the initial view suggested by the file. You can try another processed result that has not been opened, or switch readers for cross-validation.

3. Are page thumbnails the same as PDF bookmarks?

No. Thumbnails are image previews of each page, usually arranged in actual page order; bookmarks are a text navigation structure established inside the document and can include chapter levels and jump targets. For scanned PDFs without bookmarks, displaying thumbnails can still help with page lookup; for documents with a clear structure and existing bookmarks, bookmark navigation can be selected according to reading needs.

4. Will this function convert PDFs into images?

No. The purpose of selecting "Show page thumbnails" is to modify the navigation panel preference when the PDF is opened, not to output image files such as JPG, JPEG, PNG, or BMP. The processed results should still be managed and delivered as PDF files.

5. Can PDFs with different page counts be put into the same batch?

From the perspective of operational logic, this task sets a unified initial view, rather than splitting or merging files according to a fixed page count. Therefore, PDFs with different page counts can be added to the processing list. However, to ensure reliable results, files from different sources, structures, and page counts should still be spot-checked.

6. What preparations should be made before processing important files?

It is recommended to back up the original files, save the processing results to a separate directory, and confirm that the files are not occupied by other software. If a PDF has an open password, editing restrictions, electronic signatures, or other special protections, the processing experience for ordinary files may not fully apply. Test with copies first and check the validity of the processed results.

7. Why is it not recommended to change the zoom ratio and page layout at the same time?

The navigation panel, page layout, and default zoom are different settings. The current need is only to expand thumbnails by default. If other options are modified at the same time, the PDF may open with unexpected single-page, continuous-page, or zoom effects. Minimizing changes according to requirements is more conducive to controlling the results of batch processing.

V. Summary

To uniformly expand the left page thumbnails by default for multiple PDFs, you can use the "Set PDF Initial View" feature in HeSoft Doc Batch Tool . The operation process is: enter PDF Tools and open the corresponding function, add files or import a batch of PDFs from a folder, enable "Open to," select "Show page thumbnails," then set the save location and start processing.

This method is suitable for batch organizing reports, contracts, manuals, training materials, and scanned archives. Compared with manually setting each file one by one, it can consolidate repetitive operations into a single parameter configuration and a single batch processing task, while reducing the probability of missed file changes. It is recommended to first test with a small number of PDF copies, confirm in a commonly used reader that the left thumbnails can be displayed automatically, and then import the formal files for batch execution.