Website troubleshooting is a technical support service that finds the root cause of a site that will not load, returns error codes, or has a broken form, checkout or booking flow, using server logs and the code itself, and then fixes it for good. When your website is not loading, we respond within 4 hours. We work on WordPress, custom PHP, Node.js / Next.js and static HTML sites.
When a website will not load, the cause almost always sits in one of three layers: the domain and DNS, the server (hosting), or the site's own code. The error message tells you which layer to look at first; the table below maps the symptoms we see most often to their likely causes.
| Symptom | Likely cause | Where to look first |
|---|---|---|
| Site does not load at all, "server not found" | Wrong DNS record, expired domain, suspended hosting account | Domain registration and DNS |
| 500 Internal Server Error | Code error, broken server configuration (.htaccess), PHP version mismatch | Server error log |
| 502, 503 or 504 error | Application process has crashed (Node.js), server resources exhausted, timeout | Process manager and resource usage |
| Blank white page | Fatal PHP error hidden from the screen, memory limit exceeded | PHP error log |
| "Your connection is not private" SSL warning | Expired certificate, failed auto-renewal, mixed HTTP/HTTPS content | Certificate and redirects |
| Contact form emails not arriving | Server mail function instead of SMTP, missing SPF/DKIM, spam filtering | Mail log and DNS records |
| Checkout or booking fails part-way | Expired API key, change on the provider's side, JavaScript error | Browser console and API responses |
| Layout broken on mobile | CSS conflict, stale cached file, newly added content | Device testing and cache |
The MDN HTTP status code reference explains what each status code means in detail.
Four quick checks will tell you within minutes whether the problem is on your side, in the network or on the site. None of them can break anything.
If all four checks come back clean, if the error code starts with 5, or if a revenue flow such as checkout or bookings has stopped, it is time to call a specialist. Google explains in its Search Central documentation that persistent 5xx errors slow down crawling and can eventually drop pages from the index.
Troubleshooting takes four steps; a fault confined to one layer is typically resolved within 1 working day, and problems spanning several layers within 2 to 3 working days. In an emergency we respond within 4 hours. If the site is completely down, we get it back online first; the permanent fix is then tested on a copy of the site (staging), with a backup taken beforehand, and deployed at a low-traffic hour.
We hear the symptoms, obtain server, admin and if needed repository access, and take a backup before touching anything
Server and application logs, DNS, SSL and recent changes are examined, and the root cause is written down
The fix is tested on the copy; related flows such as forms, checkout and login are checked before it goes live
What broke and why, what was done, and recommendations to stop it recurring are delivered in writing
Troubleshooting is a one-off job; for sites on a monthly maintenance plan it is not charged separately.
| Task | One-off fix | With monthly maintenance |
|---|---|---|
| Log review and root-cause analysis | Included | Included |
| DNS, SSL and redirect fixes | Included | Included |
| Code-level debugging (PHP, Node.js, JavaScript) | Included | Included |
| Form email, SMTP, SPF and DKIM setup | Included | Included |
| Checkout, booking and API integration repair | Included | Included |
| Written root-cause report | Included | Included |
| Continuous uptime monitoring and early warning | Not included | Included |
| Hacked site clean-up | Quoted separately | Quoted separately |
| New feature development | Not included | Not included |
| Hosting and domain renewal fees | Not included | Not included |
If the fault is the result of an attack, the work moves to Website Security & Malware Removal; a repair made without finding the entry point does not last.
Three variables set the price: how many layers the fault spans, the platform the site runs on, and whether server and code access are readily available. An expired SSL certificate and a payment error in an undocumented booking system do not involve the same workload, so we quote after a review rather than from a fixed price list.
The initial review is free; the quote is fixed after it and does not go up later. Even in an emergency we tell you what we will do and what it costs, and start once you approve.
We troubleshoot WordPress / WooCommerce, custom PHP, Node.js / Next.js and static HTML sites; the platform decides where the diagnosis starts.
On closed platforms such as Wix, Shopify or Squarespace there is no access to server logs or code, so what we can do is limited. We can help with the domain, DNS, integrations and platform settings; beyond that we refer you to the platform's own support team.
We build the same kinds of systems we troubleshoot from scratch, so we look for the weak point by knowing the architecture rather than guessing. The projects below were developed by Zep Bilişim and represent the component types where faults most often appear.
Hiding an error message is not fixing the error. Any fix made without a written root cause brings the same fault back with the next update.
Troubleshooting is carried out by Caner Zep Çelik, founder of Zep Bilişim. As Founder & Technical Consultant he has worked on custom software, WordPress and server configuration since 2020 and has been involved in more than 100 projects. He reads the logs and makes the fix himself, and does not subcontract the work.
If the problem only appears on your own computer or network, or your host has announced a general outage, you do not need troubleshooting. If faults keep recurring and appear somewhere different each time, regular monitoring under Website Maintenance & Support costs less than repairing them one by one.
Some of the sites we have built on different platforms. You can see them all on our references page.
Custom Software · News Portal · Media
Custom-built digital news portal for the shopping mall, retail and commercial real estate sector: categories, headline slider, search, subscriptions and KVKK-compliant cookie consent.
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Web Design · Booking · Tourism
Corporate website with a booking system for an Istanbul airport luxury transfer service.
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Web Design · Healthcare · Booking
Modern, appointment-focused corporate website design and development for a pediatric and occupational therapy center for children.
$ visit_site →When a website is not loading, the cause is usually in one of three places: an expired domain or wrong DNS record, hosting that is suspended or out of resources, or an error in the site's code. First try the site on mobile data from another device, then check the domain expiry date and your hosting account. If those are clean, the server log needs examining.
A 500 error means the server hit an unexpected problem while handling the request, and the real cause is written in the server error log. The most common causes are a broken .htaccess configuration, a PHP version mismatch and a code error introduced by a recent update. Changing files without reading the log makes diagnosis harder; rolling back the last change is often the quickest first step.
A blank white page usually means a fatal PHP error that is hidden from the screen, or an exceeded memory limit. The error log in your hosting account shows which file stopped on which line. On WordPress sites the trigger is usually a plugin or theme update; on custom software, old functions that stop working after a PHP version change are common.
This warning usually means the SSL certificate has expired or automatic renewal has failed. The certificate is renewed, checked to cover both the www and non-www versions of the domain, and any HTTP links on the page are switched to HTTPS. If the warning persists while the certificate is valid, the problem most likely lies in a redirect or in mixed HTTP/HTTPS content.
Form emails are often sent through the server's own mail function without authentication, so they land in spam or never arrive. The fix is to send them via SMTP and add SPF and DKIM records to the domain. First check your spam folder and whether the form shows a success message after sending; if it does not, the problem is in the form itself.
In an emergency we respond within 4 hours. A fault confined to one layer is typically resolved within 1 working day, while problems affecting DNS, the server and the code together take 2 to 3 working days. If the site is completely down, we get it back online first and then make the permanent fix, tested on a copy of the site.
Ongoing backups, updates, monitoring and monthly reports on every platform, plus website takeover.
View details → Website Maintenance & SupportWe clean hacked sites, close the entry point and hand over a root-cause report.
View details → WordPress SupportFast help for WordPress sites hit by plugin conflicts, blank pages or a broken update.
View details →Written by: Caner Zep Çelik, Founder & Technical Consultant · Last updated: