SumatraPDF Recently Read Files Missing: How to Fix It

If the SumatraPDF Home tab is empty, familiar documents have disappeared from the frequently read list, or the list resets after every restart, the PDF files themselves are usually not damaged. The most likely causes are disabled history tracking, a hidden Home tab, settings that cannot be saved, privacy software deleting SumatraPDF data, or documents being opened from temporary locations. The steps below isolate those causes without confusing recent-file tracking with session restoration or last-page memory.

1. Confirm the Symptom With One Simple Document Test

Start with a controlled test instead of repeatedly opening files from email, a browser, a ZIP archive, or a cloud application. Those sources can create temporary copies whose paths later disappear, making the recent list unreliable even when SumatraPDF is recording history correctly.

1. Create a folder such as C:\PDF-Test.
2. Copy one ordinary, unrestricted PDF into that folder.
3. Open SumatraPDF normally, then open the test document from inside the application.
4. Read or navigate through several pages and close the document.
5. Close SumatraPDF completely, reopen it, and inspect the Home tab or frequently read list.

If the test document appears and remains after another restart, recent-file tracking works. Stop changing SumatraPDF settings. The original problem is probably tied to the source location or cleanup process affecting the missing documents.

If the test document never appears, continue to the history and Home tab settings. If it appears until SumatraPDF closes but disappears at the next launch, focus on settings-file persistence, permissions, portable mode, and cleanup tools.

1.1 Separate Recent History From Other Features

Several SumatraPDF behaviors can look related but are not identical. The frequently read list records documents for convenient reopening. Session restoration controls whether previously open tabs or windows return. Per-document state can remember information such as the last viewed page. A document may reopen at its last page without appearing on the Home tab, or it may appear in history without being restored as an open tab.

For this problem, success means that a stable local test document appears in the frequently read or Home list and remains there after SumatraPDF is closed and reopened. Do not use last-page memory alone as proof that the history list is fixed.

2. Check the Settings Directly Related to Recent Files

2.1 Verify RememberOpenedFiles

The most important setting is RememberOpenedFiles. Open SumatraPDF's advanced settings and locate that entry. It should be set to true when you want SumatraPDF to retain opened-file history.

If it is set to false, change it to true, save the advanced settings file, return to SumatraPDF, and repeat the controlled local-document test. Close and reopen the program afterward. Success means the test file now appears and survives a restart.

If the setting already says true, do not toggle unrelated display, rendering, or session options. Move on to checking whether the Home tab is hidden and whether the settings file can actually retain changes.

2.2 Check for NoHomeTab Confusion

The NoHomeTab setting can hide the Home tab. When that option is enabled, the missing Home interface may create the impression that SumatraPDF deleted its history even when opened-file information still exists.

Set NoHomeTab to false if you want the Home tab displayed. Depending on the interface and configuration, frequently read documents may also be reachable through a menu even when the Home tab is hidden. Check both places before concluding that history has been erased.

Success means the Home tab becomes available and shows the expected list. If the interface returns but remains empty after opening the controlled test PDF, continue troubleshooting history persistence.

2.3 Avoid Commands That Intentionally Clear History

SumatraPDF supports command-line behavior that can intentionally forget opened files. A shortcut, script, launcher, kiosk setup, or support utility may start SumatraPDF with an option designed to clear saved file history. Inspect the shortcut you normally use by opening its properties and checking the Target field after the executable path.

If you find a history-clearing argument such as -forget-opened-files, remove it unless clearing history is intentional. Also check scheduled scripts or desktop-management tools that launch SumatraPDF for you.

Success means files remain in the list after launching SumatraPDF from the corrected shortcut. If launching the executable directly preserves history but the usual shortcut does not, the shortcut or launcher is the cause.

3. Check Windows, Document Sources, and Portable Mode

3.1 Test Files From Permanent Local Locations

Documents opened directly from a browser download preview, email attachment, compressed archive, scanning utility, or temporary export directory may receive disposable paths or changing filenames. SumatraPDF can record the path it was given, but it cannot keep a useful entry when another program deletes or replaces that temporary file.

Save the document to Documents, Downloads, or another permanent folder before opening it. If the saved copy appears consistently while the attachment or preview copy does not, SumatraPDF is working correctly. Use permanent copies for documents that you expect to revisit.

Network shares, removable drives, and cloud-synchronized folders add another variable. The list may contain an entry, but reopening can fail while the drive is disconnected, the share is unavailable, or a cloud placeholder has not downloaded. Test the same file from a local folder before resetting any settings.

3.2 Confirm Which SumatraPDF Copy Windows Opens

Windows file associations can launch a different SumatraPDF executable from the one opened through your Start menu or desktop shortcut. This commonly happens when both an installed copy and a portable copy exist. Each copy may use a different settings location, so their recent lists can differ.

1. Open SumatraPDF from the shortcut you normally use and note its executable location if available.
2. Double-click the controlled PDF in File Explorer.
3. Check whether the same installed or portable copy opened.
4. Use Windows default-app settings to assign the intended SumatraPDF executable to PDF files if necessary.

Repeat this check for other supported formats you regularly use, such as EPUB, MOBI, CBZ, CBR, CHM, DjVu, XPS, or image formats. A format association may point to another reader or another SumatraPDF copy.

Success means opening a file from File Explorer and opening it inside SumatraPDF both update the same history list. Stop once that behavior is consistent.

3.3 Check Portable Mode Permissions

A portable SumatraPDF copy generally keeps its writable data near the executable. Problems arise when it is placed in a protected folder, read-only network location, optical media, restricted USB drive, or directory where the current Windows account cannot create and update files.

Move the portable folder to a user-writable location, such as a folder under Documents, and run it normally. Do not use administrator mode as a permanent workaround because that can create a separate permission context and conceal the real problem.

After opening the test PDF, close SumatraPDF and look for an updated settings file and associated cache data in the portable folder. Success means their modification times change and the document remains listed after relaunching the same executable.

3.4 Treat Rendering and Printing as Separate Symptoms

Codecs, Ghostscript, printer drivers, and external conversion tools are generally not responsible for an empty recently read list. They become relevant only when a particular format will not open, render, convert, or print. If an ordinary local PDF opens correctly but is not retained in history, focus on settings persistence rather than installing rendering components.

Likewise, document permissions and DRM restrictions may limit copying, printing, or other actions, but they should not be bypassed. Test with an unrestricted local PDF to separate document-specific limitations from history tracking. If only one unusual document fails to open, solve the format or access issue lawfully rather than resetting the entire recent-file database.

4. Inspect or Reset SumatraPDF-settings.txt Safely

SumatraPDF stores preferences and saved state in SumatraPDF-settings.txt. An installed copy commonly keeps its data under the current user's local application data area, while a portable copy may keep it beside the executable. A related sumatrapdfcache folder can hold cached data used by the application.

To open the installed-data location quickly, press Windows key plus R, enter %LOCALAPPDATA%\SumatraPDF, and press Enter. If the folder is absent, verify that you are using an installed copy and that you are looking under the same Windows account that runs SumatraPDF.

4.1 Check Whether the Settings File Is Writable

Close every SumatraPDF window before inspecting the file. Editing it while the application is running can cause your changes to be overwritten when the program exits.

• Confirm that SumatraPDF-settings.txt is not marked read-only.
• Check whether its modified time changes after you open a test document and exit SumatraPDF.
• Verify that your Windows account has permission to modify the containing folder.
• Make sure security software is not blocking the executable from writing there.
• Compare the path with the executable you are actually launching.

If the file timestamp updates and the test document persists, stop. The settings store is functioning. If the file never changes or changes are immediately reversed, investigate permissions and cleanup software before deleting anything.

4.2 Look for Privacy and Cleanup Tools

Privacy cleaners, system optimizers, endpoint-management products, logon scripts, and automated profile cleanup can remove recent-document records or application cache folders. Some tools classify reading history as privacy data and erase it during sign-out, shutdown, scheduled maintenance, or browser cleanup.

Temporarily exclude the SumatraPDF settings directory from the cleaner, or disable only the rule that removes SumatraPDF history. Then open the controlled PDF, close the program, run or wait for the usual cleanup event, and reopen SumatraPDF.

Success means the entry remains after the cleanup event. Re-enable other cleanup features one at a time if needed, but preserve the SumatraPDF data location when you want recent-file tracking.

4.3 Reset Without Destroying the Only Copy

If the settings file is writable but appears corrupted or internally inconsistent, close SumatraPDF and rename SumatraPDF-settings.txt to something like SumatraPDF-settings.backup.txt. Rename the cache folder to sumatrapdfcache.backup rather than deleting it. Launch SumatraPDF and allow it to create fresh data.

This is an intentional reset, not a restoration. A fresh file cannot reconstruct history that was already deleted. Its purpose is to determine whether new history can be saved reliably. Your previous preferences may also return to defaults.

Open the controlled PDF and restart SumatraPDF. If it now remains in the recent list, the previous state file or cache was involved. Reapply necessary preferences manually instead of copying the entire old file back, which could restore the problem. Keep the backup until you confirm that all important settings have been recreated.

5. Run a Clean Temporary Test Before Reinstalling

Reinstalling is often ineffective because an installer may leave per-user settings in place. A cleaner diagnostic is to run a separate portable copy from a new writable folder without reusing the existing settings file.

1. Download SumatraPDF only from its official website.
2. Place the portable files in a new folder under Documents.
3. Do not copy old settings or cache files into that folder.
4. Open the same controlled local PDF.
5. Close and reopen that exact portable executable.

If the recent entry remains, the application can track files correctly on this Windows account. The likely cause is the original profile, settings path, launcher, cleanup rule, or folder permission. You can repair that environment or continue using the clean portable copy.

If the clean copy also loses the entry, repeat the test after disabling only relevant cleanup or security rules. Also verify that the folder remains writable and that you are reopening the same executable. Reinstallation should be considered only after these checks, particularly if the executable itself is damaged or missing.

6. Quick Fix Checklist

• Open a normal PDF saved in a permanent local folder.
• Confirm RememberOpenedFiles is true.
• Set NoHomeTab to false if you expect to see the Home tab.
• Check both the Home tab and the frequently read menu.
• Remove intentional history-clearing arguments from shortcuts or scripts.
• Confirm Windows file associations launch the expected SumatraPDF copy.
• Give portable mode a writable folder outside protected system directories.
• Check whether SumatraPDF-settings.txt updates after exit.
• Exclude SumatraPDF data from privacy cleanup when history should persist.
• Rename settings and cache data before testing a fresh state.
• Use a clean portable test before reinstalling.

Stop troubleshooting as soon as one controlled local document remains in the list across restarts and across your normal method of launching SumatraPDF. Additional resets can erase useful preferences without improving a working setup.

7. Frequently Asked Questions

7.1 Why Is the Home Tab Missing Entirely?

The Home tab may be hidden by the NoHomeTab setting. Set it to false if you want that interface visible. A hidden Home tab does not necessarily mean history has been deleted, so also inspect the frequently read list available through the application's menus.

7.2 Why Does the List Reset Every Time I Close SumatraPDF?

This usually means the settings file cannot be updated, another SumatraPDF copy uses a different data location, or a cleanup tool removes the saved state. Check the modification time of SumatraPDF-settings.txt, folder permissions, portable mode location, and privacy-cleaning rules.

7.3 Can SumatraPDF Restore a Recent List That Was Deleted?

Not automatically. Resetting settings creates a clean history store but does not reconstruct deleted entries. A backup of the previous settings file may contain old saved state, but restoring the complete file can also restore the fault that caused the issue. Keep backups and test new history before attempting selective recovery.

7.4 Why Are Email Attachments or Browser Documents Missing?

Email clients and browsers often open documents from temporary folders. Those copies may be renamed or deleted after the application closes. Save the file to a permanent local folder first. If that copy remains in the list, recent-file tracking is working as intended.

7.5 Does Remembering the Last Page Prove That Recent History Works?

No. Last-page memory, session restoration, and the frequently read list are related forms of saved state, but they are not the same feature. Verify recent-file tracking by checking whether a test document appears on the Home tab or frequently read list after a full restart.

7.6 Will Reinstalling SumatraPDF Fix a Missing Recent List?

Not necessarily. Per-user settings can survive reinstallation, and portable copies may continue using their existing local settings. A fresh portable test in a new writable folder provides a more useful diagnosis. Reinstall only after confirming that settings, permissions, launch shortcuts, and cleanup tools are not causing the reset.