File Permissions and the Error You Cannot Explain

The error that makes no sense

A page returns forbidden. A folder that worked yesterday will not serve anything. An upload fails with a message about not being able to write.

Nothing has been changed, the file is visibly present in the file manager, and the error is not about the file being missing.

That combination is almost always permissions, which is a concept that never comes up until it does, and then explains several things at once.

It is also one of the few technical subjects where a rough understanding genuinely helps a business owner, because the symptoms are recognisable and the cause is narrow.

What permissions are

Every file and folder on a server carries settings describing who may do what with it.

There are three actions: read it, write to it, and run it. And three groups: the owner, a group, and everybody else.

The web server is frequently in the everybody else category, which is why a file readable by you can still be unreadable by the server serving your site.

Those settings are usually written as three digits, which is where the numbers people quote come from, and the numbers are the reason this looks more complicated than it is.

The two symptoms

• Forbidden errors: something is not readable enough.
• Upload or save failures: a folder is not writable.
• A blank page where a script should run.
• Images missing while the page itself loads.
• Everything failing after a migration or a restore.

The last is by far the most common cause of somebody encountering this at all, because copying files between servers frequently does not preserve the original settings.

Migrations are the usual trigger

Worth knowing, because it explains why this appears suddenly on a site nobody touched.

Moving a site between hosts, restoring from a backup, or extracting an archive can reset permissions to whatever the process defaults to.

The site then works partially: pages load, images do not, uploads fail, or one folder returns forbidden while the rest is fine.

That partial failure is characteristic and is a strong indication of what happened.

Whoever performed the migration can usually correct it in a few minutes with a bulk change, and it is a reasonable thing to raise with them rather than something you caused.

The conventional settings

Given in outline, because knowing roughly what is normal helps you tell whether something is odd.

Folders are conventionally set so the owner can do everything and others may read and enter them.

Files are conventionally set so the owner can read and write, and others may only read.

Anything more permissive than that, particularly anything writable by everybody, is a security concern rather than a fix, even though it makes an error go away.

The specific numbers vary by host and by configuration, which is why the useful instruction is to match what the working folders on your own server use rather than to apply a value from an article.

A worked example

A business migrated to a new host and the site appeared to work, so the migration was declared finished.

Over the following fortnight two things emerged: nobody could upload an image, and one section of the site returned forbidden.

Because the site was mostly fine, nobody connected the two symptoms, and they were reported separately as a broken uploader and a broken page.

The host identified it in about ten minutes as permissions not preserved during the transfer, and corrected the whole tree.

Both problems disappeared together, which was the confirmation.

The useful lesson was that a migration is not finished when the homepage loads, and the check afterwards should include an upload and a walk through every section.

What not to do

The specific bad advice this subject attracts.

Setting everything to fully open makes almost every permissions error disappear, which is why it is widely suggested and why it appears to work.

It also allows anything running on that server to write to your files, which on shared hosting is a genuine exposure and is the route by which sites get modified without anybody logging in.

Do not apply a blanket permissive setting across the site, and be wary of any instruction to do so.

If a folder genuinely needs to be writable, make that folder writable rather than everything.

When it is not permissions

Worth ruling out, since forbidden errors have other causes.

A security rule or firewall blocking a request, which produces the same message for a different reason.

A configuration file denying access to a directory deliberately.

A missing index file, where the server refuses to list a folder's contents and reports forbidden rather than not found.

And a plugin or security tool restricting access to an area intentionally.

The distinguishing question is whether the problem is one folder or the whole site, and whether it started after a migration, an update, or nothing identifiable.

The counter-case

This is not a subject a business owner needs to administer.

Changing permissions is a legitimate way to break a site or to open it up, and the tools to do it in bulk sit in the same file manager as everything else.

The value of understanding it is diagnostic rather than practical: recognising the symptom, describing it accurately, and knowing it is a routine fix rather than a serious fault.

That turns a support conversation from something is broken into uploads fail and one folder returns forbidden since the migration, which is most of the way to a fix.

Recognise it, report it precisely, and let whoever maintains the site apply the change.

What to do

1. Note whether it is one folder or the whole site.
2. Note when it started, and what happened then.
3. Check whether uploads also fail.
4. Suspect a recent migration or restore first.
5. Compare against a working folder rather than a number online.
6. Never apply a blanket permissive setting.
7. Describe both symptoms when you report it.

Step seven is what shortens the fix, since the two symptoms together identify the cause immediately and separately they look like two unrelated faults.

Getting hold of what you are entitled to is covered in owning the files at the end.

Frequently asked questions

West Coast Media Solutions Inc. provides web design, web development, hosting, digital marketing, and business consulting to organisations across Canada, drawing on more than twenty-five years in the field.