Common Migrator Errors
From Joomla! Documentation
This page lists common migrator errors and their solutions
MySQL: Unknown column 'x' in 'field list'
This is usually caused by having a third party extension installed on your Joomla! 1.0 site that has hacked the core Joomla! tables and added new fields. If the extension in question has been properly written, uninstalling it should resolve the problem. If it doesn't, identifying the table that has the extra field in it and removing this field will resolve this issue.
Examples of extensions that are known to do this (incomplete):
An alternative solution to this problem is to manually remove that particular column from the table in question. I'd personally recommend first examining your Joomla! site and seeing which extensions you have installed, potentially creating a test site using JoomlaPack, and seeing which extension caused the issue. When you find extensions that cause issues, please add them to the list on this page.
MySQL: Column count doesn't match value count at row 1
Solution pending. If you know of the answer, please contribute it here!
This occurs when you have incorrectly specified a prefix or you previous entered the incorrect prefix and haven't replaced your SQL file. The prefix for all migrations is "jos_" which is replaced when the SQL file is created. Keep in mind that you need to replace the migrate.sql file before each migration with a clean file as the migrate.sql file is changed in the process.
MySQL: Duplicate entry '1' for key 1
This usually occurs with a message about either the menu or modules table. This is caused by one of two things: the wrong prefix is entered or the files are unwriteable. If you put in the wrong prefix, replace the migrate.sql file with a new copy and enter the prefix "jos_". If the files are unwriteable, ensure that the installer can write to the following locations:
- your temporary directory (usually the 'tmp' folder in your install)
- the folder "installation/sql/migration"
- [optional] the entire "installation" folder and subfolders (you will remove them later anyway)
If you have previously tried migrating and have an existing migrate.sql file (regardless of your upload method), try deleting it first, validating that it is gone and then reupload (either via FTP or HTTP) the migration SQL file and then migrate with the permissions set accordingly.
404 - Component not found
This can occur immediately post migration and on the home page. This is typically caused by having a menu link set as the default link which points to a component that is no longer installed. For migration this means that you've had a non-core component as the default home page. To work around this try creating a new menu link to a piece of content (an article link) and making it the default and see if your site appears properly when you view it.