calibre Preferences Not Saving: How to Fix It

When calibre preferences are not saving, the usual symptom is simple: you change a setting, close calibre, open it again, and discover that the old value has returned. The cause is often a configuration folder that calibre cannot write to, a cloud-sync conflict, an unexpected portable configuration location, an unclean shutdown, or security software blocking file changes. However, some apparent preference failures are actually library-specific settings, device options, conversion choices, plugin behavior, or command-line overrides. The steps below help you identify which category applies, make one controlled change at a time, and stop as soon as the setting survives a restart.

1. Confirm the Symptom With a Small Safe Test

Begin with a harmless setting that is easy to recognize. Do not start by changing conversion defaults, deleting files, resetting plugins, or moving your library. A small test tells you whether calibre has a general configuration-writing problem or whether only one feature is affected.

1. Open calibre normally.
2. Go to Preferences and change a minor interface option that you can easily reverse.
3. Select Apply if the dialog provides that button, then select OK.
4. Wait for active jobs to finish.
5. Close calibre using its normal Exit or Quit command.
6. Wait several seconds, confirm that calibre has closed, and start it again.
7. Return to the same preference and check its value.

Success means the test setting remains changed after a complete restart. If it does, calibre can probably write at least some general preferences. Stop making system-level changes and investigate the specific feature that keeps reverting.

If the test preference also reverts, the problem is probably broader. Continue with the configuration folder, shutdown, security, portable installation, and clean-profile checks below.

1.1 Make Sure You Are Restarting the Same Installation

Some computers have more than one calibre installation or shortcut. For example, a Windows user may have a normal installation and calibre Portable, while a Linux user may have packages installed through different methods. Each launch method can use a different environment or configuration location.

Start calibre from the same shortcut you normally use, open the calibre configuration folder from Preferences, and note its location. Close calibre, launch it using the shortcut you are testing, and open the configuration folder again. If the location changes, you have found an important clue: you are not testing the same profile.

Success means repeated launches point to the same configuration folder. Once that is confirmed, stop switching shortcuts while troubleshooting.

2. Check Whether the Setting Is Actually a Global Preference

Not every option displayed by calibre belongs to the same settings store. Before treating the problem as a general calibre issue, identify what is reverting and where that value is supposed to live.

2.1 Library and Metadata Settings

Custom columns, saved searches, virtual libraries, book metadata, and some library behavior are associated with a particular library rather than the global calibre interface. If calibre opens a different library after restart, it may look as though settings disappeared.

Check the library name and path before and after restarting. Use the library switch menu to select the intended library. If the library lives on removable storage, confirm that the drive is mounted under the same path or drive letter before opening calibre.

For metadata that appears to revert, check whether a metadata download, plugin, device sync, or later import is replacing it. Edit one unimportant field on a test book, close the metadata dialog, restart calibre, and inspect that same book before running other operations.

Success means calibre reopens the same library and the test metadata remains unchanged. Stop changing global preferences if only one library or metadata workflow is affected.

2.2 Conversion Options

The options shown in a conversion dialog can come from general defaults, saved settings for a particular book, or values selected for the current conversion. Changing an option for one conversion does not necessarily redefine the default for every future book.

Test with one book and distinguish between changing a global conversion default and changing the current book's conversion settings. After saving the intended default, close the dialog, reopen it for a book that does not already have customized conversion settings, and verify the value.

Success means the intended option appears in the correct context. If it works for new books but not an older title, the older title may have book-specific conversion settings rather than a preference persistence failure.

2.3 Device and Send-to-Device Options

Device settings may belong to the active device driver and can be available only while the device is connected. A different USB mode, a changed mount point, or a device being detected through another driver can make the options appear to reset.

Reconnect the same device using the same USB mode and cable. Wait for calibre to detect it, then open the device configuration from the device menu. Change one safe option, save it, disconnect through the operating system when appropriate, close calibre normally, and test again.

Success means the same device is detected in the same way and its option remains selected. If detection changes between sessions, troubleshoot the connection before editing more preferences.

2.4 Email, Content Server, and Network Options

Email delivery and Content server settings may fail for reasons that do not involve saving. A stored email account can remain present while authentication, provider policy, network access, or firewall rules prevent it from working. Similarly, the Content server can retain its options but remain unreachable from another device.

First check whether the values themselves disappear after restart. If they remain visible, the problem is operational rather than a preference-saving failure. Review the relevant job details, server log, authentication settings, and firewall access. Do not disable the entire firewall as a test. If necessary, allow only the trusted calibre application on the appropriate private network.

Success means the values survive restart and the feature works during a direct test. Once persistence is confirmed, stop resetting the account or server configuration and focus on connectivity.

2.5 Plugins, Viewer, Editor, and Command-Line Options

A plugin can maintain its own configuration and may not use the same files as calibre's general preferences. Test whether the problem occurs with a built-in option or only inside one plugin. If it is plugin-specific, check for an Apply, Save, or OK button in the plugin dialog and test without performing unrelated updates.

The E-book viewer and Edit book tool also have settings that are separate from some main calibre preferences. Confirm the behavior in the exact component where you changed it.

Command-line options are different again. A shortcut, script, service definition, or shell command can supply an option every time calibre starts. That option can override what you expect from the graphical interface. Check the shortcut target, launch script, environment variables, and service command if the problem occurs only when calibre is launched in a particular way.

Success means the setting persists when calibre is opened normally. If it changes only under a script or plugin, stop altering the main configuration and troubleshoot that component.

3. Check the Configuration Folder and Operating System

calibre stores its general configuration in a configuration folder. The most direct way to locate the active folder is to open Preferences, go to the advanced miscellaneous area, and use the option that opens the calibre configuration folder. This is safer than assuming a default path because portable installations, environment variables, and customized setups can redirect it.

3.1 Verify Configuration Folder Permissions

Close calibre before modifying folder permissions. In your file manager, inspect the active configuration folder and confirm that your user account can create, modify, rename, and delete files there. A practical test is to create a small text file in that folder, rename it, and then remove it. Do not edit calibre's configuration files manually during this test.

On Windows, check the folder's Security properties and confirm that your current account has normal write and modify access. On macOS, use Get Info to review Sharing and Permissions. On Linux, inspect the folder's ownership and permissions, especially if calibre was previously run as root or through a different user account.

Avoid routinely running calibre as an administrator or as root. Doing so can create configuration files owned by another account, which may make later normal launches unable to update them.

Success means your regular account can write to the folder and a test preference survives a clean restart. Stop changing permissions once that happens.

3.2 Close calibre Cleanly

Preferences may not be written correctly if calibre is repeatedly terminated by a forced shutdown, task manager, system crash, session kill, or sudden removal of a portable drive. Active jobs can also delay shutdown.

Finish or cancel jobs intentionally, close viewer and editor windows, and exit calibre through its menu. Wait until the process has ended before shutting down the computer, signing out, disconnecting a portable drive, or restarting calibre.

If an icon or window disappears but the process remains active, use debug logging before forcing it closed. A plugin, device connection, or background task may be delaying shutdown.

Success means calibre exits fully and the changed preference is present at the next launch. If clean shutdown fixes the problem, no reinstall is needed.

3.3 Pause Cloud Sync for the Configuration Test

A configuration folder inside OneDrive, Dropbox, iCloud Drive, a synchronized home directory, or another cloud-managed location can experience conflicts. A sync client may restore an older copy, create a conflict file, or update files while calibre is closing.

Pause synchronization temporarily, close calibre, change one test preference, exit cleanly, and reopen calibre. If the setting now persists, resume syncing only after deciding whether the configuration folder should be moved to a normal local location.

The calibre library requires similar care. calibre's documentation warns against network filesystems and says that calibre and a file-sync tool should not access a library at the same time. Google Drive is specifically identified as incompatible with a calibre library. A library-sync problem is not always the same as a global preference problem, but both can look like settings or state reverting.

Success means the preference survives while synchronization is paused. Stop testing unrelated settings and resolve the sync location or scheduling conflict.

3.4 Check Windows Controlled Folder Access and Antivirus

Windows Controlled Folder Access can block an application from changing files in protected locations such as Documents or Desktop. Third-party antivirus products may provide similar ransomware protection.

Open Windows Security and review Protection history or ransomware protection notifications for a blocked calibre executable. If calibre was blocked, use the controlled-folder interface to allow the legitimate installed application. Add only the specific trusted executable instead of disabling antivirus or ransomware protection globally.

If a third-party security product is installed, review its event history, quarantine, application control, and protected-folder settings. Use a narrow exception only when the log shows that the legitimate calibre application was blocked.

Success means no new block event appears and the test preference remains after restart. Once confirmed, keep the broader security protection enabled.

3.5 Verify the Portable Configuration Location

calibre Portable is self-contained and keeps its settings and libraries together in the portable folder. Therefore, changing preferences in a normal installation does not necessarily change the portable copy, and the reverse is also true.

Make sure you launch the portable executable inside the intended calibre Portable folder. Confirm that the folder is writable and is not on read-only media. Do not unplug the drive until calibre has completely closed. If the portable folder is under aggressive cloud synchronization, copy it temporarily to a writable local folder and repeat the safe preference test.

The portable edition also remembers libraries differently. Official calibre guidance notes that a library opened outside the portable folder may not be remembered after restart. If the apparent problem is that calibre Portable forgets the selected library, place that library inside the portable folder rather than treating it as a failed global preference.

Success means the same portable executable opens, the expected configuration is used, and the test setting or supported library location survives restart.

4. Use Logs and Focused Diagnostics

Logs are most useful after you have reproduced the problem once with a specific setting. They are less useful when many preferences, plugins, devices, and libraries have been changed simultaneously.

4.1 Run the Main Interface in Debug Mode

calibre can run its graphical interface with debugging enabled. You can start debug mode from calibre by right-clicking the Preferences button, or use the documented keyboard shortcut. Advanced users can launch the interface with the calibre-debug -g command.

Start debug mode, change one test preference, close calibre normally, and review the generated output for permission errors, configuration write failures, plugin exceptions, or shutdown problems. Do not assume every warning is related. Focus on entries generated at the time you saved or closed the application.

Success means the debug session closes without a relevant write error and the preference persists. If a specific plugin fails near shutdown, test with that plugin disabled before changing the entire configuration.

4.2 Review Jobs and Feature-Specific Output

If the issue involves conversion, news downloads, metadata retrieval, email delivery, or sending a book to a device, open the completed or failed job and inspect its details. A failed operation can leave preferences intact while making it seem that calibre ignored them.

For device detection problems, calibre-debug includes a device-driver debugging option. Use it when a device is not detected consistently or appears under the wrong driver. Conversion problems can also be isolated with conversion debug output, but that is appropriate only when conversion behavior is the symptom.

Success means you can identify whether the setting was lost or the operation merely failed. Stop resetting preferences once the log shows a network, file, device, or source-book error.

5. Test With a Fresh Configuration Before Reinstalling

A fresh configuration test is one of the fastest ways to separate a damaged profile from an installation, operating system, or library problem. It should be done carefully so the existing configuration remains available.

1. Back up the existing calibre configuration folder.
2. Close calibre and confirm that no calibre process remains active.
3. Rename the configuration folder rather than deleting it.
4. Start calibre and complete any initial setup using a temporary empty library in a normal local folder.
5. Change one harmless preference.
6. Exit calibre cleanly and start it again.
7. Check whether the preference survived.

Do not point this test at your main library if you want complete isolation. Do not install plugins, connect devices, enable the server, or copy old configuration files into the new folder before completing the restart test.

If the setting saves in the fresh profile, the calibre installation can write preferences. The cause is likely inside the old configuration, such as a damaged file, plugin, conflicting customization, or unexpected override. Restore the old folder if needed, then disable or remove suspected components one at a time. Alternatively, rebuild the profile gradually while keeping the backup.

If the setting still does not save in a fresh profile, investigate folder permissions, security software, environment variables, launch methods, and forced shutdown behavior. Reinstalling calibre may replace program files, but it usually does not correct an unwritable or redirected configuration location.

5.1 Check for a Redirected Configuration Directory

calibre supports the CALIBRE_CONFIG_DIRECTORY environment variable, which tells it where to read and store configuration files. A script, managed workstation policy, shell profile, or previous customization may set this variable.

Open the configuration folder from within calibre and compare it with the location you expected. If an environment variable redirects it to a read-only, missing, synchronized, or temporary folder, correct the launch environment or choose a stable writable location. Users on managed computers may need help from their administrator.

Success means calibre consistently uses one writable configuration folder and the safe preference test survives restart.

6. Quick Fix Checklist

• Change one harmless preference and restart calibre before testing anything else.
• Confirm every launch uses the same calibre installation and configuration folder.
• Exit calibre normally and wait for all processes and jobs to finish.
• Verify that your user account can write to the active configuration folder.
• Pause cloud synchronization during the persistence test.
• Check Windows Controlled Folder Access and antivirus block history.
• Confirm portable calibre is running from a writable portable folder.
• Determine whether the option is global, library-specific, device-specific, or plugin-specific.
• Check command-line options and the CALIBRE_CONFIG_DIRECTORY environment variable.
• Run calibre in debug mode and reproduce only one failed save.
• Test with a renamed old configuration and a fresh temporary profile.
• Do not delete or rebuild your main library to fix a preference-writing problem.

Stop changing settings as soon as one controlled test survives a full restart. At that point, repeat the test once more, restore any temporarily paused security or sync protection safely, and return to normal use.

7. Frequently Asked Questions

7.1 Why Do calibre Preferences Reset Every Time I Restart?

The most common explanations are an unwritable configuration folder, a security tool blocking changes, cloud synchronization restoring older files, a forced shutdown, or calibre opening a different profile. Test one minor preference, close calibre cleanly, and confirm the active configuration folder before reinstalling.

7.2 Where Is the calibre Configuration Folder?

The safest way to find the active location is from calibre itself. Open Preferences, go to the advanced miscellaneous settings, and select the option to open the calibre configuration folder. This shows the folder actually being used, including when an environment variable or portable installation has changed the normal location.

7.3 Will Reinstalling calibre Fix Preferences That Will Not Save?

Not necessarily. Reinstallation can repair missing program files, but it may leave the existing configuration folder and its permissions unchanged. Run a fresh configuration test first. If a new profile saves settings correctly, rebuilding or repairing the old profile is more relevant than reinstalling the application.

7.4 Can I Delete the calibre Configuration Folder?

Renaming and backing it up is safer than deleting it. A renamed folder lets calibre create a clean configuration while preserving plugins and old settings for later examination. Keep your library folder separate and untouched. The configuration test should not require deleting books or the library database.

7.5 Can Cloud Storage Make calibre Settings Revert?

Yes. A cloud client can restore an older configuration file or create a conflict while calibre is closing. Pause syncing and repeat the test. Cloud and network storage can also affect the library itself, which is a separate but related risk. Keep active configuration files local when possible and never let a sync tool modify an open calibre library.

7.6 How Do I Know the Problem Is Fixed?

The fix is successful when the same setting remains selected after two clean restarts from the same calibre shortcut, with no permission or security block reported. If the affected feature also works in a direct test, stop troubleshooting. Additional resets, reinstalls, or library changes would add risk without providing useful evidence.