[Forum] Inline image displaying as links - old posts only!

[Pottsy]

Here's an odd one....

On old posts, inline images appear as "attachment 123" text link only. Images are in a pile at the bottom.
If you create a new post in that old thread, images display inline (thumbnail or full size according to ACP setting) correctly.

Editing the old post makes no difference.
Rebuild posts makes no difference.

Any clues?
vb 4.2.1, browser independent, default style, no vbseo, mods off.

[Pottsy]

One other thing - if you edit the post (by adding one character), it then displays correctly. But when you refresh the page, it displays links again. The edit is still there though.

[Pottsy]

Fixed. If you copy a thread and the OP has used [ATTACH]1234[/ATTACH] to insert the pics, then it all fails since the pics are copied with new numbers too.