Hosting & Control Panels

Changing a database host can leave cached DNS, connection pools, firewall rules, or application settings pointing to the old server. The site may fail only on pages that query the database. What to check Verify the configured hostname and port, DNS resolution from the web account, remote database privileges, firewall allowlist, TLS settings, and...

A website may choose a language from browser headers, cookie state, application defaults, cached pages, or a control-panel configuration. Visitors can receive inconsistent content even though translations are installed. What to check Compare request language headers, cookies, user preferences, cache keys, application fallback rules, and...

A hosted website may load locally but fail when calling an external API because of DNS, outbound firewall restrictions, TLS trust, PHP settings, or provider allowlists. The failure may affect only one endpoint. What to check Check application logs, DNS lookup from the account, TLS certificate validation, outbound connection settings, host policy, API...

A website can accept text forms while file attachments fail because of upload limits, temporary storage, account quotas, permissions, or a security rule. The form may still show a generic success message. What to check Check PHP and application upload limits, temporary directory capacity, account disk and inode use, destination permissions, and...

Switching a PHP handler can change process ownership, extensions, worker behavior, and configuration inheritance. A site may then fail on specific routes even though the selected PHP version remains unchanged. What to check Compare the previous and current handler, PHP-FPM pool, loaded extensions, file ownership, per-directory settings, and error logs....

A domain may report a different PHP version than expected if its handler, document root, or account-level setting differs from the version selected in the panel. What to check Check the domain’s assigned PHP handler, MultiPHP settings, subdomain document root, and any local configuration that overrides the handler. Use a temporary diagnostic page only...

A scheduled task may run with a different working directory, PATH, PHP binary, or permissions than an interactive shell. This can make a job fail or modify files as an unexpected account. What to check Review the cron owner, exact command, absolute paths, selected PHP version, environment, and file ownership. Capture output to a protected log and avoid...

A mailbox may stop receiving mail because it reached quota, a filter moved messages, DNS points elsewhere, or the receiving server deferred delivery. What to check Check mailbox and account quotas, mail delivery logs, filters, MX records, and the sender’s SMTP response. Preserve a sample timestamp and recipient while avoiding disclosure of message...