Identifying a problematic hook
You suspect that a custom module, addon or hook might be causing a problem for your installation.
Here's how you go about finding which one is causing the issue.
Disable all hook files
The first step is to temporarily disable all the hook files from your system.
To do this, connect to your site using FTP or SSH and navigate to the /includes/hooks/ directory.
Create a folder called excluded_hooks and move all of your hook files into it. This will prevent them from loading.
Verify the issue you are trying to resolve in your installation is resolved.
Now to identify which hook is causing the problem, navigate into the directory you just created and move the hook files back to the /includes/hooks/ folder one at a time.
After moving each hook back, verify if the issue has returned.
When the issue does return, the last hook file you returned to the /includes/hooks/ directory is the cause of the issue.
You should continue to debug that hook or contact the vendor of it if from a third party.