Error: Trying to upgrade to 4.0

Trying to upgrade from 3.8.4 to 4.0 and in the upgrade script showing this database error?

Database error in vBulletin 3.8.4:

Invalid SQL:
INSERT INTO cron
(nextrun, weekday, day, hour, minute, filename, loglevel, varname, volatile, product)
VALUES
(1232082000, -1, -1, 5, 'a:1:{i:0;i:0;}', './includes/cron/sitemap.php', 1, 'sitemap', 1, 'vbulletin');

MySQL Error : Duplicate entry 'sitemap' for key 2
Error Number : 1062
Request Date : Monday, December 21st 2009 @ 01:35:27 AM
Error Date : Monday, December 21st 2009 @ 01:35:27 AM
Script : vBulletin Upgrade System - Radar Detector Reviews &amp Radar Detectors Forum Radar
Referrer : vBulletin Installer - New Installation
IP Address : 98.200.123.114
Username :
Classname : vB_Database
MySQL Version : 5.0.85-community-log

Check that you don't have multiple sitemap tasks in your task manager. Older versions of vbseo required a manual task creation and may be left over. If so, you should delete one of the tasks.

where is the task manager located at?

VB ACP -> Secheduled Taks -> S. Tasks Manager
vBSEO Sitemap Generator is the only one you want there. If there's another one in there, delete the task.

hmm that is the only one on there

What if you access the table cron directly from phpmyadmin? Do you see two different crons listed with sitemap as the varname?

Sorry to butt into this thread but I'm having the exact same problem. I have two crons listed for sitemap with two different varnames, vbseo_sitemap_task and one which just says sitemap.

Which one should I delete? The one that just says sitemap as a varname?

The easiest thing to do is to delete both, and then re-import the vbseo sitemap product file. It will re-create the correct task.

Thanks Brian, I've deleted the one with varname 'sitemap' and that has at least got me past step 3 in the upgrade. Now I'm stuck on step 9 due to a MySQL Error : Illegal mix of collations (latin1_german2_ci,IMPLICIT) and (latin1_swedish_ci,IMPLICIT) for operation '='
Error Number : 1267

I don't suppose you could help me with that could you?

I have limited experience with charset issues.... Sounds like you have german characters going into or translating over into a new table that doesn't support those characters. You may need to consult vb support.

Thanks Brian, will do.