Sykoi said:
Table './DB/table' was created with a different version of MySQL and cannot be read
Any ideas on how I can fix this?
Since you downgraded MySQL without taking a full dump and then restore of databases, this is very likely to happen. The error message is self-explanatory.
If you have a backup, dump the database, and then restore it into 4.1.x.
It is a very good idea, before MySQL upgrade/downgrade, is to have backups, to be on the safe side.
If you go to:
http://dev.mysql.com/doc/refman/5.0/en/downgrading.html at the bottom of the page, you'll read:
"These steps are given in The normal symptom of a downward-incompatible table format change when you downgrade is that you can't open tables. In that case, use the following procedure:
1- Stop the older MySQL server that you are downgrading to.
2- Restart the newer MySQL server you are downgrading from.
3- Dump any tables that were inaccessible to the older server by using mysqldump to create a dump file.
4- Stop the newer MySQL server and restart the older one.
5- Reload the dump file into the older server. Your tables should be accessible.