Core files can be corrupted by a failed update, a disk problem, or a compromise. Reinstalling core replaces them with known-good copies from WordPress itself. Done properly it touches nothing but core — your database, uploads, themes and plugins are untouched. Done carelessly it takes customisations with it, which is why it is worth doing carefully.
WordPress core reinstall without data loss
Core files are damaged or missing. We reinstall WordPress core cleanly, leaving your content, plugins, themes and uploads exactly as they are.
- Full backup taken before we start
- If we can’t fix it, you get your money back
- We never ask for your own password
This or something else?
| Core files damaged or checksums failing | This fix covers it |
| Update failed and left files half-written | Fatal PHP error after update |
| Blank page with no obvious cause | White screen of death |
| Files changed by an intrusion | Security remediation, not this |
| Only a plugin or theme is broken | Plugin conflict diagnosis |
What you are seeing
- Errors naming files inside wp-admin or wp-includes
- A failed update that left core in an inconsistent state
- A security scanner reporting core files that do not match checksums
- Behaviour that makes no sense given the plugins installed
Common causes
- An update interrupted before it finished replacing files
- A file transfer or migration that dropped or truncated files
- Disk corruption or a full disk during a write
- Direct edits to core files that a later update partially overwrote
- Files modified by an intrusion, which needs security work as well
What we do
- Take a full backup of files and database before touching anything
- Verify core file integrity against official checksums to see what actually differs
- Reinstall core cleanly, preserving wp-config, uploads, themes and plugins
- Check for anything that was placed in core directories where it should not be
- Confirm the database schema matches the core version
- Load-test every template and the admin
What is included
- Core files matching official checksums exactly
- Content, uploads, plugins and themes untouched
- A note on what was damaged and, where determinable, how
- The pre-fix backup, kept for 30 days
Not included
- Malware removal or intrusion cleanup, if damage turns out to be deliberate
- Preserving direct edits to core files — those are removed, and we tell you first
- Recovering content that was already lost before we started
- Design changes or content work
Questions about this fix
Will I lose my content?
No. Content lives in the database and uploads live in wp-content — neither is touched by a core reinstall. That separation is exactly why this is a safe operation when done properly.
What if someone edited core files deliberately?
Then those edits are removed, because that is the point. We check first and tell you what we found, so if a previous developer put something important there you know before it goes. Core edits should be moved into a plugin anyway.
Could this be a hack rather than corruption?
It can be, and modified core files are a common sign. We look at what changed and how. If the pattern points at an intrusion we stop and tell you, because reinstalling core without cleaning the rest just hides the problem for a few days.
Is this the same as clicking Reinstall in the admin?
Only if the admin still works and the damage is limited. That button replaces core files but will not tell you what was wrong, will not check the database schema, and cannot run at all if the site is down.
Will this fix the vulnerability that let a hack happen?
No, and that's an important distinction — reinstalling core replaces the files, it doesn't close whatever door let someone in. If compromise is suspected, that needs its own security pass alongside this.
Related fixes
If this is the second time this year
A bad update breaking the site is a symptom of updates not being tested first. Care plans run every update on a staging clone before it reaches your live site, which is the actual fix for this happening again.
Your access, your rules
Create a separate admin account for us and delete it when we are done. For anything else, we get in touch and agree a method — never a form field on this site, never by reply to an email.
We back up first, always
Before anything is touched we take a full backup and keep it for 30 days. If a fix goes wrong, we put the site back exactly as it was.
If it is not what you bought
If the problem turns out smaller than what you ordered, we refund the difference. If it is bigger, we stop and send a quote before doing any extra work.
If we cannot fix it
You get back what we received. Diagnosis is on us — you only pay when the problem is actually solved. The payment processor takes its fee before the money reaches us, so we never hold it and it is not ours to return. That is true here as everywhere else.
If it comes back
Reply within seven days of delivery and we put it back on the bench at no cost. The fix is not finished until it holds.
What we are responsible for
If something goes wrong with a fix, our responsibility is limited to what you paid for it. We take a full backup first so mistakes can be undone, and we tell you before doing anything outside what you bought.