XF 1.5 Error: Requested Resource Could Not Be Found

[TheLaw]

I'm finally in the process of upgrading but this is a remarkably baffling error that I see has made it's way into XF 2.0 - and is unclear as to the source. I can reproduce the error but I can't explain how and why it is occurring. While I've seen that this error is related to a server issue, I'm now at the point where I question whether this is the source of the issue as you'll see below.

A routine post was posted here. Trying to edit, reply or do anything (other than read) a simple post in a thread results in the following error:

Not Acceptable​

​

An appropriate representation of the requested resource could not be found on this server.​

A moderator recreated the post with the same words and it results in the same error: https://www.thelaw.com/threads/nc-out-of-state-judgement-cfspartan.81875/

So then I (as the grand administrator wizard) created the same post, using the same magic words, but pasted into a plain text editor to ensure hidden characters were not contained in the post... and my post also cannot be edited, deleted, modifed, etc.! https://www.thelaw.com/threads/nc-out-of-state-judgement.81881/

So... I created a new thread in the same subforum using the same prefix just with a different title and different text... and that works fine: https://www.thelaw.com/threads/bad-debt-collection-out-of-state.81882/

I created a duplicate of the thread this time - but I used a different title. That worked. But once I changed the title of the thread to the same title of the thread that was giving me a problem, I received this error.

NC Out of State Judgement

NC resident. I am potentially subject to a significant judgment from out of state (KS). NC DOL website says that wages are not garnished for judgments...

www.thelaw.com

So this leads me to believe that the error may not be a server or permissions related error but something else that is in conflict relating to the thread title.

 

[Max Taxable]

Not AcceptableAn appropriate representation of the requested resource could not be found on this server

This sounds like it comes from an add-on, not xenforo itself. Just off the cuff.

Here's what it looks like.

 

[Paul B]

It's due to a server security mechanism.

 

[TheLaw]

It's due to a server security mechanism.

Brogan - thanks, I've done the research on the forum and I've read that. But what server security mechanism would be triggered by changing a thread name to have the same name as the problem thread? I see nothing in my logs and I can't understand what plain text in a thread title should make a difference. It's just this "NC Out of State Judgement" - if the thread title is different, the thread works just fine.

 

[Max Taxable]

Brogan - thanks, I've done the research on the forum and I've read that. But what server security mechanism would be triggered by changing a thread name to have the same name as the problem thread? I see nothing in my logs and I can't understand what plain text in a thread title should make a difference. It's just this "NC Out of State Judgement" - if the thread title is different, the thread works just fine.

It can't be generated by xenforo since there are no such phrases in xenforo.

 

[Paul B]

But what server security mechanism would be triggered by changing a thread name to have the same name as the problem thread?

It will be mod security or something similar.

It's a false positive but the host will be able to whitelist to prevent it happening.

 

[TheLaw]

It can't be generated by xenforo since there are no such phrases in xenforo.

It will be mod security or something similar.

It's a false positive but the host will be able to whitelist to prevent it happening.

@Max Taxable - software can trip someting that generates an error message elsewhere.

@Brogan - Thanks for the quick reply. I'm going to have a look but am still interested in understandable how plain text entered into the title of a thread would create any type of positive error. I'll report back what I discover.

A fix for the issue in this instance is as follows - recreating the post with the title slightly changed (state at the end works fine) and then changing the poster ID to the actual poster. I'm not sure how to delete the thread yet but it can be hidden and the entire problem is solved.

 

[Max Taxable]

Max Taxable - software can trip an error message generated elsewhere.

I was unable to duplicate your issue on my dev site, test board or on any of the live action xF sites I admin. For what that's worth.

 

[Paul B]

am still interested in understandable how plain text entered into the title of a thread would create any type of positive error

Enjoy.

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