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XF 1.5 Significant Problem with v1.5.3


Active member

I recently just installed (upgraded) to the v1.5.3 maintenance release and one on my members tried to post with the link in it below and all hell broke loose.


For whatever reason the below pops up and it's caused a significant problem. I've had Auto Link Rebuild installed for some time and when I went into tools and tried to run it the same type of error happens and it screws everything up and gets caught in an unfinished task state. Even if I restore My SQL from a backup and uninstall that add-on the same thing happens again when I try to make a post with the same link.

Anyway, how to correct this?

An exception occurred: preg_match(): Delimiter must not be alphanumeric or backslash in /home/me/public_html/library/XenForo/Helper/Media.php on line 56

preg_match() in XenForo/Helper/Media.php at line 56
XenForo_Helper_Media->_convertMediaLinkToEmbedHtml() in XenForo/Helper/Media.php at line 39
XenForo_Helper_Media::convertMediaLinkToEmbedHtml() in XenForo/BbCode/Formatter/BbCode/AutoLink.php at line 231
XenForo_BbCode_Formatter_BbCode_AutoLink->_autoLinkUrl() in XenForo/BbCode/Formatter/BbCode/AutoLink.php at line 132
call_user_func() in XenForo/BbCode/Formatter/Base.php at line 745
XenForo_BbCode_Formatter_Base->renderValidTag() in XenForo/BbCode/Formatter/Base.php at line 652
XenForo_BbCode_Formatter_Base->renderTag() in XenForo/BbCode/Formatter/Base.php at line 565
XenForo_BbCode_Formatter_Base->renderTreeElement() in XenForo/BbCode/Formatter/Base.php at line 546
XenForo_BbCode_Formatter_Base->renderSubTree() in XenForo/BbCode/Formatter/Base.php at line 526
XenForo_BbCode_Formatter_Base->renderTree() in XenForo/BbCode/Formatter/BbCode/AutoLink.php at line 79
XenForo_BbCode_Formatter_BbCode_AutoLink->renderTree() in XenForo/BbCode/Parser.php at line 505
XenForo_BbCode_Parser->render() in XenForo/Helper/String.php at line 253
XenForo_Helper_String::autoLinkBbCode() in XenForo/ControllerPublic/Thread.php at line 515
XenForo_ControllerPublic_Thread->actionAddReply() in XenForo/FrontController.php at line 351
XenForo_FrontController->dispatch() in XenForo/FrontController.php at line 134
XenForo_FrontController->run() in /home/me/public_html/index.php at line 13
Last edited:


XenForo developer
Staff member
You have a BB code media site that isn't defined properly -- it's defined as a regex, but it's not valid. Unfortunately, the error doesn't make it clear which one, but if you have any add-ons that deal with BB code media sites, I would look at any one they have changed. (Or any ones you've added or customized.)