Could not update Activiti database schema unknown version from database 6001

This error occurs when Activiti is unable to update the database schema because the version of the database is unknown. The error message indicates that the database version is '6.0.0.1', which is not recognized by Activiti.

To resolve this issue, you can try the following steps:

1. Check the database version and compare it with the supported versions of Activiti. You can find the list of supported database versions in the Activiti documentation.

2. If the database version is not supported, you may need to upgrade or downgrade the database to a supported version.

3. If the database version is supported, you can try to manually update the schema. You can find the SQL scripts for updating the schema in the Activiti distribution.

4. If none of the above steps work, you may need to create a new database and migrate the data from the old database to the new one. This can be a complex process and should be done carefully.

It is recommended to take a backup of the database before attempting any of these steps to avoid data loss