XF 1.5 Blank page when opening threads after import


Active member
Hi all,

I just moved to XenForo and today I imported my vBulletin 4 database. The importing went without any problems and everything seems to be properly migrated.
Unfortunately I noticed that I get a blank page when trying to open an existing thread. I was happy to find the following thread, but all the suggested fixes did not work:


Thanks in advance for your help, I really appreciate it! :)

Best regards,

EDIT: When I try this with Microsoft Edge, I get an HTTP 500 error.


Active member
Hello Brogan,

thank you very much for your quick answer! Here's the error message:

ErrorException: Fatal Error: Class 'XenES_Api' not found - library/Andy/SimilarThreads/ControllerPublic/Thread.php:127

I disabled the similar threads addon and everything works fine now.
Any idea what caused the problem?