XF 1.2 Fresh install v1.2.2 - Server Error (after config accepted)


I've installed XenForo on a test server successfully, but today was attempting a fresh, clean, install of XenForo v1.2.2 on the real server, with a brand new, empty, database - and after the config.php settings have been accepted, the installation fails with a 'Server Error' reported:

I've tried dropping all the tables and re-starting and various other things (different user/password etc.)
all to no avail.

Any help to overcome this would be much appreciated, please.

Here are the server config details, in case that is important:
Screen Shot 2013-10-26 at 14.11.51.png
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You say 'the log' as if there is but one log file, are we talking about the Apache web server log or is there a XenForo log file I've yet to find?

By the way, thanks for removing the inadvertent password - grabbed the wrong screen shot. Thanks anyway :)

Apache log is clean (no errors for the installation time, previous error was grumbling about missing fav icon from the old forum s/w [vB installed to allow import into XenForo - if I can get XF to work])
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OK, as above the Apache log has no errors for the (attempted but failed) XenForo installation(s).

A search of the XenForo manual uncovers no mentions I can find of a log file - am I missing the point of your question?

The only error I can see is the one in the screen grab, ie:

Server Error
Server Error

preg_match(): Compilation failed: unknown option bit(s) set at offset 0

preg_match() in XenForo/Input.php at line 197
XenForo_Input::_doClean() in XenForo/Input.php at line 183
XenForo_Input->filterSingle() in XenForo/Input.php at line 375
XenForo_Input->filter() in XenForo/Install/Controller/Install.php at line 248
XenForo_Install_Controller_Install->actionStep3b() in XenForo/FrontController.php at line 337
XenForo_FrontController->dispatch() in XenForo/FrontController.php at line 134
XenForo_FrontController->run() in /home/[user]/public_html/xenf/install/index.php at line 18
Where else should I look for the elusive error information, please?

I'm stuck (and feeling frustrated with XenForo!)
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Liam W

Well-known member
Looks for the PHP error log - it might be called 'error_log' or something else depending on server configuration.
My fellow Admin did some digging - we have the (mis-)fortune to be using a server with cPanel/WHM and this problem is a 'known issue with EasyApache' apparently. See these links for more details:



By the way, the PHP error_log didn't appear to have anything related to the XenForo problem (it has other issues, though, so we'll get those sorted).

Thanks to everyone here who tried to help - appreciated, even if it rather looks like we are in a stale mate for now, at least we know what the problem is due to in XenForo - maybe XF can check the PCRE UTF-8 support capability to help those caught out in future, maybe?