Read the UPGRADING file in your OTRS directory.
Short summary: backup application and database
Stop services: cron, apache, postfix (?)
overwrite directory with source
setpermissions
possibly rebuild config
clear cache
restart services.
This is not intended to replace the documentation. Read it and do what it says.

OTRS 6.0.x (private/testing/public) on Linux with MySQL database.
Please
edit your signature to include your
OTRS version, Operating System, and database type.
Click Subscribe Topic below to get notifications. Consider amending your topic title to include [SOLVED] if it is so.
Need help? Before you ask