How to uniformly expand the left thumbnail by default for multiple PDFs? Methods to batch modify the open view

If a multi-page PDF requires manually expanding the left thumbnail pane every time it is opened, it can affect the efficiency of report review, contract verification, and archive retrieval. This article starts from batch office scenarios and explains how to uniformly set the opening navigation panel of multiple PDFs to page thumbnails. Use HeSoft Doc Batch Tool to import files centrally, select display page thumbnails in the PDF initial view options, then set the output location and run the process, avoiding repeated modifications for each file while keeping the reading style consistent across a batch of materials.

In daily office work, many PDF files contain dozens or even hundreds of pages, but after opening them, only the body pages appear, and the page thumbnails on the left side remain collapsed. Reviewers who want to view the table of contents, attachments, signature pages, or a specific chart need to first find the sidebar button in the reader, and then switch to page thumbnails. If only one document is processed per day, this action is hardly noticeable; however, when organizing a whole batch of project materials, contract attachments, or scanned documents, the repeated operation continues to consume time.

A more efficient approach is to batch modify the PDF open view before delivering or archiving files, so that multiple documents open with the left thumbnail panel expanded by default. This article will use the actual interface of HeSoft Doc Batch Tool to explain the complete workflow from selecting the feature and importing files to setting page thumbnails and outputting results. The software is positioned for batch office file processing, helping users reduce mechanical clicking by applying the same operation to multiple PDFs at once.

1. What problems can expanding page thumbnails by default solve

The initial view of a PDF can be understood as the display state that the document expects the reader to adopt when it is first opened. The navigation panel is an important component of the initial view, and common states include not showing the sidebar, showing bookmarks, and showing page thumbnails. Page thumbnails display the entire document as small page previews, making them suitable for navigation based on layout and visual content.

For document managers, uniformly setting thumbnails is not simply a matter of changing the interface appearance, but rather improving the entry point for using the document. Its main value is reflected in the following aspects:

• After opening a multi-page report, the overall structure of the document can be previewed without additional clicks.
• Scanned PDFs without bookmarks can also be quickly located through page images.
• When reviewing contract attachments, users can directly find table pages, stamped pages, or signature pages.
• During training and presentations, thumbnails can be used to quickly switch between chapters.
• When delivering materials in batches, the default navigation method of each PDF becomes more consistent.

This setting does not export thumbnails as separate image files, nor does it generate PDF cover previews for Windows folders. The phrase "expand thumbnails by default" in this article specifically refers to displaying the page thumbnail navigation panel in the reader interface after opening a PDF document.

2. Applicable scenarios: which PDFs need thumbnail navigation more

1. Business reports with many pages

Annual reports, feasibility studies, audit materials, and project summaries usually contain a cover, table of contents, multiple body sections, and appendices. Page thumbnails can show layout differences and make finding target content more intuitive than continuous scrolling.

2. Scanned documents without bookmarks

PDFs composed from scanners or images do not necessarily have usable bookmarks. In such cases, even if displaying bookmarks is selected, the navigation area may not contain enough content; choosing page thumbnails allows direct preview of every page.

3. Contracts and archives that need centralized delivery

The same project may include the main contract, supplementary agreements, quotations, acceptance forms, and other attachments. If all these files need to be easy to page through quickly, uniformly setting them to show thumbnails when opened can reduce the trouble of recipients adjusting the interface for each file individually.

4. Internal PDF document libraries

For rules, operation manuals, and training materials accumulated by a team over a long period, inconsistent initial views can affect the reading experience. Batch settings can help administrators standardize and organize a batch of historical documents.

3. Effect preview: comparison before and after setting

Before processing: the body occupies the main area, and thumbnails are not expanded

From the example before processing, it can be seen that the PDF reader is displaying the document body, with pages arranged continuously, but the page thumbnail panel is not open on the left side of the interface. Readers can turn pages through page numbers or the scroll bar, but cannot directly preview the layout of other pages.

When a document has only a few pages, continuous scrolling can still meet reading needs; as the number of pages increases, it becomes difficult to accurately locate content by scrolling alone. If users have to manually bring up thumbnails every time they open a document, the actual usability of the document will also depend on individual operating habits.

After processing: a list of page thumbnails automatically appears on the left

After the setting is completed, readers that support PDF initial view will display page thumbnails when opening the file. Thumbnails are arranged by page number, and the right side still shows the body of the current page, so both can be used at the same time.

This layout is especially suitable for viewing long PDFs. Users can drag the scroll bar in the thumbnail area to browse more pages, or click a thumbnail to jump directly. The screenshot shows the effect in one reader; buttons, colors, and panel width may differ in other readers, but the main goal of this operation is simply to make the page preview list appear on the left.

4. Specific steps for batch modifying the PDF open view

Step 1: Select Set PDF Initial View from the PDF tools

After launching HeSoft Doc Batch Tool , enter "PDF Tools" on the left. The tool list contains different types of PDF batch processing tasks. This time, select "Set PDF Initial View". From the interface description, it can be determined that this function is used to batch set the navigation panel, page display mode, and default zoom ratio when PDF files are opened.

Choosing the correct task entry is very important. Functions such as deleting bookmarks, modifying metadata, and PDF conversion are also related to PDFs, but they cannot replace initial view settings. The goal of this article is only to specify the navigation panel after opening, so you should enter the function indicated by the arrow in the screenshot.

Step 2: Build the list of files to be processed

After entering the task page, the top process shows four stages, in order: "Select records to process", "Set processing options", "Set save location", and "Start processing". In the first stage, you can click "Add Files", or use "Import Files from Folder".

If the PDFs are scattered in multiple locations, they can be added in batches as needed; if the files are already stored in a single directory, importing from a folder is usually more suitable for a large number of documents. After successful import, the software will display the file name, path, extension, and related time information in the list. The four PDFs in the screenshot have formed the same processing queue, and the summary at the bottom shows a total of 4 records.

Before continuing, check the names and paths one by one. Cases where file names are the same but paths differ are common in project materials, and judging only by name can easily lead to selecting the wrong file. If a record does not belong to the current task, it can be removed from the list through the delete icon in the operation area of that row. After confirming the list, click "Next".

Step 3: Set the open navigation panel to show page thumbnails

The second stage is used to set the actual processing parameters. First enable the "Show when opening" switch, and then select "Show page thumbnails" among the three radio options below it. Do not mistakenly select "Do not show sidebar" or "Show bookmarks": the former keeps the navigation bar hidden, while the latter opens the bookmark panel rather than the page preview list.

In the screenshot, "Show page thumbnails" is already selected, indicating that the target parameter setting is complete. The "Page display mode" and "Default zoom mode" below are two other types of initial view parameters. If there is no need to unify page layout or zoom ratio, these can be left off, and only the necessary item should be changed. In this way, the goal of expanding thumbnails by default can be achieved while avoiding changing other reading preferences originally set in the file as much as possible.

Step 4: Choose the save location for the processing results

Click "Next" to enter the save location settings. When batch processing important files, it is recommended to output the results to a new folder rather than replacing the source PDFs at the beginning. A clear directory can be created according to the project, such as "Project A - PDF thumbnail version" or "Archive results - initial view already set".

Saving results independently has two practical benefits: first, the opening state before and after processing can be quickly compared; second, if the parameter choices do not meet expectations, you can still return to the source files and run the process again. When setting the output location, confirm that the target disk has enough available space and that the current account has write permission.

Step 5: Start processing and verify the opening effect

After entering the final stage, start processing and wait for the software to complete the task. During execution, keep the source files and output folder accessible. Do not temporarily remove storage devices, and do not move PDFs that are being processed.

After the task ends, do not only confirm that "files were generated"; also check whether the files meet expectations. It is recommended to select one short document, one long document, one scanned document, and one PDF with charts, reopen them in a commonly used reader, and confirm whether the page thumbnails on the left appear automatically. At the same time, check whether the page count, body text, images, and attachment pages are normal. If this batch of files will be sent to clients, a compatibility test can also be performed in the reading environment commonly used by the recipient.

5. Why batch processing of office files is more suitable for large numbers of PDFs

The process of manually setting the PDF initial view usually requires repeatedly opening the properties window in each document, finding the initial view, selecting the page panel, saving, and closing. The more files there are, the more obvious the time consumption becomes, and problems such as missed changes, incorrect selections, or forgetting to save are also more likely to occur.

HeSoft Doc Batch Tool converts these repeated actions into one batch: first build a file list, then specify parameters uniformly, and finally output centrally. For dozens or hundreds of PDFs, operators no longer need to switch back and forth between multiple reader windows. Batch tasks can also keep parameters consistent, avoiding a situation where some files show thumbnails while others show bookmarks.

The core value of this method is not simply pursuing processing speed, but reducing human errors in large numbers of repetitive operations. Especially in contract archiving, project delivery, and document library maintenance, stable and unified processing rules are usually more reliable than temporary adjustments to individual files.

6. Common questions and considerations

1. Why do some readers still not automatically expand thumbnails

PDF documents can save initial view preferences, but the final display is still affected by the reader implementation and user settings. Some readers restore the interface state from the last time the document was closed, and some browser preview components may ignore part of the initial view information. It is recommended to close and reopen the file, and use mainstream desktop PDF readers for cross-validation.

2. What is the difference between page thumbnails and PDF bookmarks

Page thumbnails are visual previews of each page, suitable for finding content based on page appearance; bookmarks are chapter navigation set by the author and depend on whether the document contains a bookmark structure. Scanned files may have no bookmarks, but generally can still show page thumbnails. Therefore, the choice should be made according to actual needs, and the two should not be confused.

3. Should the default zoom mode be enabled at the same time

It is only necessary to set it separately when delivery specifications explicitly require a fixed zoom ratio or effects such as fitting page width. If the current task only requires expanding the left thumbnails by default, it is safer to keep the other switches off. The fewer parameters there are, the easier it is to judge whether the processing result meets the single goal.

4. Can the only original file be processed directly

It is not recommended to perform batch writes on the only original file without a backup. Especially for stamped contracts, electronically signed documents, long-term archives, and permission-protected PDFs, samples should be copied and tested first, and the original version should be retained. After modifying a PDF, the status of some digital signatures may be affected, so such documents should follow the document management regulations of the relevant organization.

5. How to reduce the probability of errors when there are many files

You can first verify the parameters with a small number of files, and then execute the full batch; import files in batches by project or material type; output to an independent directory; check the results by file count and names after completion; and finally spot-check PDFs of different page counts and different sources. Although batch processing adds one more management step, it makes it easier to identify problems and run the process again.

7. Summary

When multiple PDFs do not automatically show the left thumbnail panel after opening, this can be resolved by batch modifying the PDF initial view. The specific operation is: in HeSoft Doc Batch Tool , enter "Set PDF Initial View", add files or import files from a folder, enable "Show when opening", select "Show page thumbnails", then complete the save location setting and start processing.

This workflow is suitable for multi-page reports, contract attachments, scanned archives, product manuals, and enterprise document libraries. Compared with modifying documents one by one, batch processing saves time and also keeps the navigation method consistent across the same batch of PDFs. It is recommended to first select several representative files for a trial run, confirm that the reader display meets requirements, and then process the complete folder, with spot checks and backups performed before delivery.