Pages showing 404 error

[Peter Knight]

Hi guys

is there a checklist of items I should consider for diagnosing a series of pages which display a 404 error?

Basically I have built a Blog and all my posts are under a folder called 'Posts'. Some of these pages successfully display while others display a 404 page. 

This is what I have confirmed so far...

1. All pages are within the same root folder 'Posts'
2. All pages have the same template and fields completed
3. All pages have the same properties under Settings > Who can access this page
4. Pages have no redirects in place
5. Pages have no special characters or anything funky in the URL slug

There are no errors showing in the log either so I am stuck ?

Thanks

[kongondo]

24 minutes ago, Peter Knight said:

is there a checklist of items I should consider for diagnosing a series of pages which display a 404 error?

Just to add on to your list:

1. Is this happening for all users or just guests?
2. Do you have any autoload modules in place that could be interfering?
3. Do you have any hooks in place that could be interfering?
4. Single or multi-lingual site?
5. Tracy debugger errors?
6. Changes to .htaccess, i.e. some rule getting matched?

Edit

I don't think it is mod_security since you can access some pages but not others..

Edited May 13, 2020 by kongondo
added more

[Peter Knight]

Thanks @kongondo. 

I found a fix for it although I don't understand the issue root cause.

Discovered that editing the page url slug fixes this. Even if I just add an extra letter. Once the page saves, I can view it.

Not wanting to have to do this manually to 50+ pages, I wondered what would happen if I changed the name (Settings > Name) of the parent for the 50 posts. That worked too and seems to have 'fixed' the 50 pages.

It must be something related to the Page Path History module or something similar.

[kongondo]

1 hour ago, Peter Knight said:

Page Path History module

Aha. Worth keeping an eye on this then.

Thanks for reporting back.

[Robin S]

@Peter Knight, I have experienced what I think is the same issue and discovered the same quick fix as you did. I think it's caused by errors relating to the expanded file and image field properties feature and I'm trying to narrow down the exact cause so I can open a GitHub issue. To check if what you're experiencing is the same as my issue...

1. Are you running one of the latest dev versions - 3.0.154 or 3.0.155?

2. Did you create everything from scratch inside the PW version you are running now, or did you update a site that was running an older PW version, or perhaps install using a site profile that was created under an older PW version?

3. Have you seen any error messages relating to image fields when you create a new page? E.g. something about a column not found such as modified_users_id

4. Do you have the PagePaths core module installed?

[Robin S]

Here is the GitHub issue relating to the expanded file and image field properties feature: https://github.com/processwire/processwire-issues/issues/1171

This may or may not be related to what you experienced.