First, ensure that your knife is in fact broken. It may just need cleaning/ troubleshooting.
In most cases, issues with deployment are caused by dry internals or dirt and debris. We suggest you consult our Maintenance page for instructions on how to clean and care for your knife. If after cleaning and lubricating your knife still does not function properly, you may need to send it in for repair.
The first step for any warranty related issues is to create a new support ticket in our support portal: http://support.microtechknives.com/support/tickets/new
Before you do, look for any articles that may solve your issue.
Once you submit the form, you will get an email with instructions on sending your knife to us.