While upgrading one site from Drupal 4.7.x to Drupal 5.0RC1, I encountered the following error:

Fatal error: Call to undefined function: filter_xss_bad_protocol() ... includes/common.inc on line 837

After much online research, file verification and a database restore, I found the problem: a typo.

When running http://example.com/update.php at the end of the upgrade, I made a typo and entered http://example.com/updates.php in the URL entry field of my browser.

Lesson learned: If you encounter the error above, check for typos. I hope this writeup helps the next person to make this typo...


chrisd’s picture

This post should be way more visible.

Took me 30 minutes to finally find this great post!

I was typing upgrade.php...silly me....


Marco Palmero’s picture

Funny... simple mistake and yet I fall into the same trap. Thanks!

marcopolo ---
Blog Marco | Best Designed Drupal Websites | Share Trading |

vitovonantwon’s picture

FROM `pojack1_drpl1`.`system`
LIMIT 0 , 30

I was getting this error. FOr some reason my filter module was inside the forum module.
I moved it out into the main modules section and got this error.
Using phpmyadmin I searched for filter and found it in system.
THere all the modules paths are listed. I changed the path from forum/filter/filter.module to /filter.module

The site works error gone.
Hope this helps.


eMPee584’s picture

i just experienced this (and other undefined function errors), and as this post pointed my nose to the system table i spotted the filter module strangely having a '0' in the status column. How this core module got disabled is way beyond me, but in case you hit this, better take a look.

devildog’s picture

Mad props to "eMPee584" for pointing me in the correct direction. Sure enough the status of my filters module was turned off, set it to "1" and we were G2G

justinkuto’s picture

Same problem here, the filter module status for some unknown reason was set to 0. Changing it to 1 fixed the problem

Yoshi’s picture

This error showed up unexpectedly while I was changing up Domain Source module and I resolved it by changing the weight to -10 in the system table, though I'm still working on my Domain Source issue.

awelch’s picture

I am still running a Drupal 6 site! yay. Anyway, I resolved this problem by checking the existence of the function in bootstrap.inc - filter_xss_bad_protocol() didn't exist (as the error specified) so I downloaded the last drupal 6 files and uploaded the bootstrap.inc file from that (which does include filter_xss_bad_protocol() )