Fatal error: Call to undefined function: formatmentionslink() in /home/somewhere/textpattern/lib/txplib_misc.php(429) : eval()’d code on line 172

Fatal error: Call to undefined function: checkcommentsallowed()

These and similar errors immediately after an upgrade are usually caused by one of two things:

  • Old plugins that haven’t been updated to work with the current version of Textpattern
  • Not updating or uploading all of Textpattern’s files correctly. Make sure you upload all the files in all subdirectories.

Similar errors immediately after installation usually indicate:

  • An incorrect txpath setting in config.php. The value automatically detected by the setup process is almost always correct, so don’t change it unless you know what you’re doing.
  • Textpattern .php files that are missing or in the wrong location.