Troubleshooting Common Limit Login Attempts Plugin Issues: PHP Errors, Conflicts, and More
Content
The 'Limit Login Attempts' plugin is a popular tool for securing WordPress login pages, but like any software, it can sometimes run into issues. Based on community reports, here are some of the most common problems and their potential solutions.
1. PHP Errors and Deprecation Notices
Users on newer versions of PHP (e.g., 8.2.x) often report deprecation warnings, while others encounter various PHP warnings that can fill error logs and affect performance.
Common Errors:
PHP Deprecated: explode(): Passing null to parameter #2 ($string) of type string is deprecated...PHP Warning: Illegal offset type in isset or empty...PHP Warning: Cannot modify header information - headers already sent...- Notices about deprecated functions like
get_userdatabylogin.
Why it happens: The plugin code may not be fully compatible with the latest PHP versions, which have stricter standards and deprecate older functions.
Potential Solutions:
- Check for an Updated Fork: The original 'Limit Login Attempts' plugin has not been updated for several years. A popular, maintained fork called Limit Login Attempts Reloaded exists, which has resolved many of these PHP compatibility issues.
- Temporarily Disable Debugging: If the errors are only notices and not breaking your site, you can disable their display by setting
WP_DEBUG_DISPLAYto false in yourwp-config.phpfile. However, this does not fix the underlying problem.
2. Plugin Conflicts Causing Login Issues
Conflicts with other plugins are a frequent source of problems, often manifesting as missing messages, blank error boxes, or functionality that suddenly stops working.
Common Symptoms:
- The login error div (
<div id="login_error"></div>) appears but is always empty. - No lockout or attempt messages appear on the login page.
- Warnings about missing function arguments (e.g.,
Warning: Missing argument 2 for limit_login_track_credentials()). - Social login plugins or security plugins like WebsiteDefender break the login process.
Why it happens: Other plugins, especially those that also modify the login process (e.g., security plugins, social logins, maintenance mode plugins), can interfere with how 'Limit Login Attempts' hooks into WordPress and displays messages.
Potential Solutions:
- Conflict Test: Deactivate all other plugins and switch to a default WordPress theme (like Twenty Twenty-One). If the problem resolves, reactivate your plugins one by one to identify the culprit.
- Check Plugin Settings: Some security plugins have options to hide login error messages. You may need to adjust these settings to allow 'Limit Login Attempts' messages to show.
- Whitelist Check: If the plugin seems to have "stopped working," verify that your IP address hasn't been accidentally whitelisted by a companion plugin, preventing you from seeing its security features in action.
3. Fatal Error: Cannot Redeclare Function
This critical error completely breaks a site, preventing access to both the front end and the admin dashboard.
Symptom: Fatal error: Cannot redeclare limit_login_setup()...
Why it happens: This occurs when the plugin is loaded twice. The most common scenario is having the plugin installed both as a regular plugin (/wp-content/plugins/) and as a must-use plugin (/wp-content/mu-plugins/), sometimes automatically by a managed hosting provider.
Potential Solution:
- Use FTP or your hosting provider's file manager to access your site's files.
- Navigate to
/wp-content/plugins/and delete thelimit-login-attemptsfolder. If your host manages a must-use version, this should be sufficient to resolve the conflict and restore site access.
4. Security Concerns and Outdated Software
Many users express concern that using an outdated plugin poses a security risk.
Potential Solutions:
- Verify Vulnerability Reports: Carefully check any vulnerability reports to ensure they apply to this specific plugin and not another with a similar name (e.g., "WP Limit Login Attempts"). Community members often note that many reported issues were patched in the last official version (1.7.2).
- Consider an Alternative: For peace of mind, consider switching to a actively maintained alternative like the previously mentioned Limit Login Attempts Reloaded or another reputable login security plugin.
When troubleshooting, always remember to clear your browser cookies and cache, as the plugin relies heavily on cookies to track login attempts. If you are unsure about any steps, particularly editing files, it is advisable to create a full backup of your site first.
Related Support Threads Support
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[Plugin: Limit Login Attempts] Minor compatibility issues with WebsiteDefenderhttps://wordpress.org/support/topic/plugin-limit-login-attempts-minor-compatibility-issues-with-websitedefender/
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Limit Login Attempts version 1.7.1 is not working with WordPress 3.4.1.https://wordpress.org/support/topic/limit-login-attempts-version-171-is-not-working-with-wordpress-341/
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login_error div content not showinghttps://wordpress.org/support/topic/login_error-div-content-not-showing/
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using deprecated functionhttps://wordpress.org/support/topic/using-deprecated-function/
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PHP 8.2.x Deprecate alert.https://wordpress.org/support/topic/php-8-2-x-deprecate-alert/
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Limit Login Attempts generating PHP errorshttps://wordpress.org/support/topic/limit-login-attempts-generating-php-errors/
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security issuehttps://wordpress.org/support/topic/security-issue-146/
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ERROR: The inserted fields are invalid.https://wordpress.org/support/topic/error-the-inserted-fields-are-invalid/
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Suddenly stopped work?https://wordpress.org/support/topic/suddenly-stopped-work/
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Plugin – Not working?https://wordpress.org/support/topic/plugin-not-working-106/
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"Fatal error: Cannot redeclare limit_login_setup()"https://wordpress.org/support/topic/fatal-error-cannot-redeclare-limit_login_setup/
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Conflicts with WordPress Password Expiryhttps://wordpress.org/support/topic/conflicts-with-wordpress-password-expiry/
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Securityhttps://wordpress.org/support/topic/security-47/
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Installed OK but no prompt at loginhttps://wordpress.org/support/topic/installed-ok-but-no-prompt-at-login/
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Plugin Vulnerabilityhttps://wordpress.org/support/topic/plugin-vulnerability-1/
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[Plugin: Limit Login Attempts] Empty login error div shown at all timeshttps://wordpress.org/support/topic/plugin-limit-login-attempts-empty-login-error-div-shown-at-all-times/
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Warning: Missing argument 2https://wordpress.org/support/topic/warning-missing-argument-2-5/
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Doesn't work with Social Login plugin anymore, please helphttps://wordpress.org/support/topic/doesnt-work-with-social-login-plugin-anymore-please-help/
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Sowing captcha without codehttps://wordpress.org/support/topic/sowing-captcha-without-code/
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Plugin May Need Updating For Latest WP Releasehttps://wordpress.org/support/topic/plugin-may-need-upfdating-for-latest-wp-release/
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Security Warninghttps://wordpress.org/support/topic/security-warning-10/
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throws an errorhttps://wordpress.org/support/topic/throws-an-error/
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Plugin hackedhttps://wordpress.org/support/topic/plugin-hacked-1/
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Cannot modify header informationhttps://wordpress.org/support/topic/cannot-modify-header-information-208/
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Plugin slows down the WP installationhttps://wordpress.org/support/topic/plugin-slows-down-the-wp-installation-2/