i need help creating a custom page hook

[Marwan Mohamed]

hello whmcs

am not very good at English but i will try my best to explain what i want to do.

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i need help to create a hook for a custom error page and show it  for a specific part of the website instead of the default internal error page.

for example lets say a client requested to view the invoice with an invalid invoice id by default whmcs will show him the ops page (the internal error tpl at /templates/example/error/internal-error.tpl)

 

 

what i want to do is show a different error page for this specific  error on the invoice page instead of the default one (/templates/example/error/internal-error.tpl)  when an invalid invoice id is provided, i want to show a custom page or a custom tpl without having to edit the default internal-error.tpl itself

 

for example this is what i want to show for customer when they get invalid invoice id error