Attached images becoming 'Unknown Attachments'.
Asked by SB:

Hello,

When I open certain pages with attached images in 'Edit' mode, I find that the images are replaced by 'Unknown Attachment' placeholder text even though they've been physically attached to the page.

The funny thing is that if I proceed to save the page, the images are permanently replaced by the 'Unknown Attachment' placeholder text in View mode. The only way to retrieve them in this case is to revert the page to its previous version, and reattach the images before saving the page.

What could be causing this?

Thanks,

Sean.


Answers:
author: Dorte Jacobsen
body: Atlassian Support has been helpful and let me know that Atlassian development has the issue (or at least a very similar one) in their short term backlog: [CONFSERVER-55928](https://jira.atlassian.com/secure/RapidBoard.jspa?rapidView=2529&view=detail&selectedIssue=CONFSERVER-55928) so there's hope that the issue will be resolved.


author: Dorte Jacobsen
body: Atlassian has fixed the "unknown attachment" issue as bug, see [https://jira.atlassian.com/browse/CONFSERVER-55928](https://jira.atlassian.com/browse/CONFSERVER-55928?)

In 7.7.3 and 7.8.0 the issue should not occur but existing pages with the issue will have to be fixed manually.


author: Arianna Royster
body: Hello! We are experiencing a similar issue. I will use the editor and publish the page with the images. Now when we go back (sometimes months later) and edit the title of the page all the attachments will then says ? unknown attachment.

We use Scroll viewport on one of our sites and we don't on the other. This issue has been in the viewport instance mostly.


author: Reinhard Mayr
body: We also encounter this problem every then and now. I found that when I switch to edit mode and then "..." button on the lower right \> *Revert to last published version* brings the images back.

Still, reason is unknown :/

comments: author: L2 Application Support
body: Hi, I?ve also tried that solution I found but it?s not working for me :(


author: Diego
body: Hello there! Great to have you in our community, [@SB](/t5/user/viewprofilepage/user-id/2286479).

What I got from your description, is that *++page attachments in specific pages become the "Unknown Attachment"++*.

I have seen this issue a few times and there is a chance that you are being affected by the following bug:

* [++***\[Confluence Server\] Attachments become 'Unknown Attachment' in the page editor with Collaborative Editing turned on***++](https://jira.atlassian.com/browse/CONFSERVER-55928)

We could try to *++turn collaborative editing off and on++*. After that, we could check if the issue is still present. Here is how to proceed.
> 1. *Click the **Cog icon** in the top right corner*
> 2. *Select **General Configuration***
> 3. *Select **Collaborative editing***
> 4. *Click **Change Mode***
> 5. *Select **Off***
> 6. ***Apply***
> 7. *Click **Change Mode** again*
> 8. *Select **On***
> 9. ***Apply***
> 10. *Check if the issue is still present*

For further investigation, would it be possible for you to give us a little more information? Here is a concise list of questions to help us better understand this situation:
> 1. *Is this affecting other types of attachments*
> 2. *Do the affected attachments have special characters in their names?*
> 3. *When did you first face this issue?*
> 4. *Which version of Confluence are you running?*

Let us hear from you, Sean! Looking forward to your reply.

comments: author: SB
body: Thanks for your response, Diego.

Turning collaborative editing on and off seemed to have no effect on the issue whatsoever. Regarding your questions:

1. No, so far it only seems to be affecting images.

2. No special characters in the name. Initially we were of the impression that solely PNG images were being affected, but this doesn't seem to be the case.

3. The issue began many months ago, somewhere around April - May, after we upgraded Confluence from 5.x.x to 6.x.x. That was the time we started missing a few missing images but it wasn't very prominent.

Last week we updated Confluence to 7.0.1, following which we started facing issues with our local server. The machine's memory modules were replaced, and that's when we started noticing more and more 'unknown attachments'.

This makes me feel that the 'unknown attachments' issue is caused by a servers-de problem more than anything, but I wouldn't know how exactly.

4. As I said, version 7.0.1.

Sean.


author: Diego
body: Thanks for keeping the thread alive, [@SBWhiskey_Me](/t5/user/viewprofilepage/user-id/2449365) !

I will now try to address some of the answers you brought to the table. Let us begin.
> *"Turning collaborative editing on and off seemed to have no effect on the issue whatsoever."*

*Are you referring to ++already problematic images (missing images)++ or even ++newly added images++ (after the off-on procedure) are affected?*

> *"3. The issue began many months ago, somewhere around April - May, after we upgraded Confluence from 5.x.x to 6.x.x. That was the time we started missing a few missing images but it wasn't very prominent."*

We could try to ++*re-index your instance*++ and check if the images are still missing. There are two types of re-indexing. One that does not require restarting the instance and a more "complete" one. Here is the documentation for both:
> * [**++\[Confluence Server\] How to Rebuild the Content Indexes From Scratch on Confluence Server++**](https://confluence.atlassian.com/confkb/how-to-rebuild-the-content-indexes-from-scratch-on-confluence-server-110035351.html)
> * ++**[\[Confluence Server\] Content Index Administration](https://confluence.atlassian.com/doc/content-index-administration-148844.html)**++

One important note is that *++rebuilding the index from scratch requires instance downtime++* . Also, while the re-index via the interface (no restart needed) *++does not require downtime++* , you and your users *++will experience a degraded performance as a result of the process++* being executed. So it is highly advisable to also schedule downtime for this procedure as well.

Let us hear from you, Sean!


author: Dorte Jacobsen
body: Hi [@SB](/t5/user/viewprofilepage/user-id/2286479) - was your "unknown attachment" issue resolved by re-indexing?

We are currently facing the exact same issue (Server 7.2.0): images that were attached and displayed in pages become "unknown attachment" when opening the editor.

This seems to happen randomly: not all pages are affected and initially we wrote it off as a user error (we have just converted from another tool and thought we had overlooked a few pages in the process).

Thanks,  
Dorte


author: SB
body: Hi Dorte,

Unfortunately I haven't had the chance to try the re-indexing method yet, as the downtime is something that would have to be coordinated with out on-site IT department.

We are noticing the missing images become more and more common though.

Sean.


author: Dorte Jacobsen
body: Thanks for getting back to me so quickly!

We had suspected this could be related to Scroll Versions - do you use that app also?

Dorte


author: SB
body: Dorte,

No not really, I doubt it's a plugin issue since we maintain two Confluence instances; one of them barely uses any plugins, and that one still seems to show broken image attachments.

Sean.


author: Dorte Jacobsen
body: Thanks for taking the time to reply :-)

We'll do some more digging to resolve the issue.

Dorte


author: SB
body: No problem.

Do leave a message here if you manage to get it sorted. :)

Thanks,

Sean.


author: Dorte Jacobsen
body: Well, reindex from scratch did NOT solve the issue.

Will let you know when/if we find the cause...

Dorte


author: SB
body: Okay, thanks for the update!

Sean,


author: Aleksandr Migun
body: We have started to experience similar issue today. Self-hosted 7.2.0. Reindexing won't help. Any ideas before raising support request?


author: Dorte Jacobsen
body: Our issue is still unresolved. We have been working with Atlassian support and they have been most helpful.

After some research, we have just agreed that the most likely cause for our issue is that we have used the unsupported plugin (<https://confluence.atlassian.com/confkb/how-to-copy-or-rename-a-space-in-confluence-169578.html>).

But there is no way to confirm this and it is worrying if you guys have not been using the unsupported plugin.

We can fix each issue manually in the affected pages but it would be a hopeless task if it just keeps appearing for some other reason...


author: Aleksandr Migun
body: We don't use any unsupported plugins, and still getting this issue.


author: SB
body: Yes, likewise.


author: Sander H
body: We're experiencing the same issue. Self hosted Confluence v7.4.0.


author: matt_bartier
body: Also have exact same issue after upgrading to v7 with certain pages...frustrating!


author: alo
body: For me the problem appeared when a user tried to upload a file with "?" in the name and the file became an "unknown attachment". Removing the attachment and then renaming the file and removing ? from the name seemed to mitigate the problem.

It's not consistent however -- there are another files, both doc and pdf, with ? in the name that's showing correctly and I could also retrieve the failed attachment from the page history or the Attachments page.

Still on 7.3.3, now upgrading to 7.4.


author: Gemma
body: This has just become a problem for me too. It was fine when I was editing last night, but this morning any images I have are being changed to unknown attachment as soon as I go to edit. Can anyone shed some light on this?


author: Dorte Jacobsen
body: See <https://jira.atlassian.com/browse/CONFSERVER-55928> - the issue was fixed in a number of Confluence versions


author: Gemma
body: Hi Dorte, thanks for this. I've been having a look and it says that this shouldn't be an issue anymore: ![image.png](https://community.atlassian.com/t5/image/serverpage/image-id/196824i25778C03FC8DC866/image-size/large?v=v2&px=999 "image.png")

As I am on the cloud version, I can only assume it's the latest updates and my page that is having the incident, was only created a few days ago. Are there any later links to this that affect the cloud version?


author: Dorte Jacobsen
body: We're on Server so I haven't really been following how Cloud is doing but I believe there's a separate issue for Cloud version.


author: Gemma
body: Thanks Dorte, I'll take a look :)


Tags: confluence-server

server